Abstract:1. It is recommended to extract the Gracilaria agar by steam in an autoclaveor an open kettle to shorten the extracting time and to facilitate the filtration. Ex-traction of Gracilaria agar under 3 lb/in² of steam pressure with 30-or 40-fold ofwater for 1 to 1(1/2) hour and then with 15-fold of water for a half hour, seemedto be more preferable (Table 1, 2,3). 2. When NaOH or KOH was used as an extracting reagent, the gel strength ofagar obtained was highly increased, and NaOH appeared to be more effective thanKOH(Table 4). The mixed reagents of NaOH and KH₂PO₄showed more marked effecton the yield of agar than did NaOH alone. But the effect of the combination of NaOHand neutral salts solution was about the same as the NaOH alone (Table 5), andvarious salts without NaOH exhibited no distinct effects (Table 6). 3. On the addition of K, Ca, Mg salts to the agar sol, their gel strength wasenbanced in spite of whether or not being heated (Table 7), while the agar sol, trea-ted with NaOH + KH₂PO₄ under 5 lL/in² of steam pressure for 1 - 2 hours, and thencooled, thawed and dried, also gave a higher gel strength with about 60% of re-covery (Table 8). 4. The extracted liquor from Gracilaria after adding alkali and heating gave ahigker gel strength than untreated, while no distinct change was observed if inorga-nic salts were added (Table 9). Our experiment on the effect of different heatingtime upon the extracted liquor treated with alkali indicated that their gel strengthincreased with the increase of heating time under 3 lb/in² of steam pressure, but theyield was relatively low. Judging from the gel strength, the treatment with 1% NaOHunder 3 lb/ in² of steam pressure for 2 hours seemed to be an optimum condition inobtaining a good quality of agar (Table 10). 5. The Oretreatment of Gracilaria with NaOH + CaCl₂ or NaOH alonet showedno marked difference in the gel strength of agar. In the alkali-treated liquor rem-ained about 10 % of agar, whick might be recovered by freezing-drying. The thalliof Gracilaria after treatment with alkali ought to be washed as thoroughly as possiblewith runniug water before the extraction to remove the alkali, or neutralized withacid, and were then subjected to extraction (Table 11).

Abstract:This paper presents a preliminary analysis on the dynamics and characters of in-dividual fecundity of Trichiurus haumela, based upon the study of 354 ovary samplesof the fish collected off East China Sea ain 1963-1964. Among the specimens measured the number of visible eggs of each individualTrichiurus haumela, in the East China Sea, ranges from 12.8-330. 9(×1,000), ge-nerally 30-50 (×1,000). The number of eggs spawned by each anal length group is33% of the number of visible eggs in that group. The number of visible eggs increaseswith body weight, anal length and age; among these three growth indices, body weightis the most important, followed by the anal length and the least being the age. The number of visible eggs of individual per aual length unit (r/l) ranges from50-650, that of per body weight unit (r/q) ranges from 52-261, generally 90-160.The relation of body weight and anal length with the number of visible eggs approa-ches a wavy curve line indicating that the variability is rather stable. This paper brings out the problem of the relation between individual fecundityand growth index. The problem of biological characteristics reflected in individualfecundity in population is also discussed.

Abstract:Based on actual surveys and observations at sea from 1959 to 1963 and refer-ences, this paper endeavores to make a preliminary study of the distribution and be-ehaviour of Enqraulis japonicus in the Hwang Hai and Po Hai, and presents methodsof its detection in the various stages of its life cycle, tius providing a means of betterexploitation of this resource. The paper describes in detail the migration and distribution of the anchovy on thefishing grounds of North China Seas, and presents biological, non-biological and com-mercial methods for its detection in regard to its biological and environmental inter-relations.

Abstract:The mating activities of the squid, Sepiella maindroni, were observed in the aq-uariums on Tsing-pan Island, Chou shan, Chekiang, under experimental conditions fromMay to June 1960 and May to July 1963 and 1964. Eyery year from April to June,the squids migrate to inshore areas for spawning. The mantle lengths of the male andfemale specimens under observation range from 7. 1 to 11.5 Cm. Copulation activities occur frequently. Postures of squids in copulation are shownin Fig. 1. From the observations we found that the male passes spermatophores tothe female's oral region. The sperm-mass is discharged and attached to the buccalmembrane and at the base of the left lateral arms of the female. The outer tuniclesof spermtophores are often formed in the female's stomach. The egg membrane is formed in the arms of the female. At first, the arms curvedown and the base of which rounds up to form a cavity into which her funnel extends,then nidamental glands and oviductal gland secrete gelatin into it to form the egg mem-brane, and finally, the egg passes through the funnel into the membrane. The black pig-ment of the egg membrane comes from its own ink sac when the egg membrane is beingformed. It seems that the fertilization of the squid's eggs takes place near the buccalmembrane.

Abstract:The present paper deals with 19 species of Myxosporidia which were collected from731 individuals belonging to 9 species of freshwater fishes in Weishan-Chaoyang andNanyang Lakes. Among these parasites, 16 species are previously known, namely: My-xidium enchelypteryii, M. orientalis, Myxosoma acuta, Myxobolus dispar, M. derma-tobius, M. cyprini, M. sqamocus, M. ellipsoides, M. migairii M. exiguus, M. gigi, M.koi, M.toyamai, Thelohanellus fuhrmanni, Henneguya sinensis, and H. doneci. Theremaining three are new species and their diagnoses are summarized as follows: 1, Myxosoma carassii sp. nov. (Figs. 9-11). On the gills of Carassius auratus(L.). The fresh spherical cysts are 0.80-0. 12 millimeters in diameter. In front view,the spore is pyriform with a somewhat hent anterior end, but it is nearly fusiform insutural view. Certain species have a thin envelope around the posterior end. The ante-rior end of the envelope expands into a cup-like structure which fits closely the pos-terior part of the spore. Its external measurements are 5. 62 (4.50-6.50) 10. 60 (9. 50-11.50)μ. The shell-valves are moderately thick and the sutural ridge is straight anddistinct. The two equal polar capsules are clongated pyriform and its coiled filamentis distinct. A small intercapsular projection is present. Dimensions of the fresh spores:leugth 15. 43 (12.50-17.50), width 10 .42 (8.75-12. 50)μ., thickness 7.94 (7.50-8.75)μ.; polar capsule 8. 30 (6.25-8.75) by 3.58 (3.12-3. 75)μ. 2, Myxobolus shantungensis sp. nov. (Figs. 25-29). On the gill rakers of Cyprinuscarpio L. The fresh cysts are spherical nodules, and surrounded by a thick layer ofconnective tissue. They are 3-9 millimelers in diameter. The spores are nearly trans-elliptical in front view and fusiform in sutural view. The shell-valves are comparativelythick at the posterior end and the sutural ridge is straight and distinct. Six to seven"V"-shaped markings are observable along the posterior half of the shell. The two eq-ual polar capsules are large and pyriform, but the polar filament is inditinct in bothfresh and stained materials. A small intercapsular projection is distinct. The sporoplasmcontains a smaller iodophilic vacuole and two nuclci. The two kidney-shaped capsulo-genous nuclei are distinct, Dimensious of the fresh spores: length 8.12 (7.50-8.75)μ, width 9.90 (9.37-10.00)μ, thickness 6.25 (5.62-6.87)μ; polar capsules 4.68(4.37-5.00) by 3.62 (3.12-3.75)μ. The iodophilic vacuole 1.90 (1.87-2.12)μ in diameter. 3, Henneguya weishanensis sp. nov.(Figs. 61-64). On the gills of Siniperca chu-atsi (Basil.). The fresh cysts are pad-like nodules in external view, measuring 3-4 millimeters in diameter, and surrounded by a thin layer of connective tissue. They con-tain four to nine small cysts which vary in size from 1.50-2.50 by 1.00-1.50millimeeters. The spores are fusiform shaped both in front and sutural views. Its anteriorendis somewhat pointed, while the posterior end prolongs smoothly into a bifurcatedtail. The sutural ridge is straight and distinct. The two pyriform polar capsules areequal in size and convergent. The intercapsular projection is indistinct. The sporoplasmcontains an iodophilic vacuole and two small nuclei. The capsulogenous nuclei are distinct.Dimensions of the fresh spores: length, including the tail 75.09 (62.50-87.00) μ,width 6.31 (6.25-6.87)μ, thickness 5.16 (5.00-5 .62)μ, length of tail 60. 10(47.50-73. 25)μ; polar capsules 4.53 (3.75-5.00) by 1.93 (1 .87-2.12)μ andiodophilic vacuole 1.20 (1. 00-1.50)μ.

Abstract:Since the initiation of haidai (Laminaria japonica) cultivation on large scale in china,several kinds of diseases have been identified, among which the most serious and most commonare the "Green Rot", "White Rot" and "Spot Rot" diseases of the thalli. A preliminary st-udy on the pathological anatomy of the diseased thalli was made and the following resultswere obtained: 1. In the parts of the thalli diseased with "White Rot", the cells were empty, havingpractically lost all their protoplasm and with no or very few chromatophores. In those disea-sed with "Green Rot", the cells had very scanty protoplasm and their chromatophores were inthe process of disorganization, appearing greenish instead of brownish as in the normal cells.No bacteria were found in the cells in the early stages of both these diseases. There fore weagree with the earlier authors that these two diseases are not caused by bacterial infection. 2. In the parts of thalli diseased with "Spot Rot", small white spots were first formed,which later grew larger and finally became large holes. Examination of the white spots re-vealed that the protoplasm and chromatophores were absent in cells, and the holes were eachsurrounded by a distinct, deeply colored ring of cells. It is our opinion that this disease, likethe above two, is not caused by bacterial infection, although in the later stages of the diseasebacterial growth may help its spread.

Abstract:A modified approach of hypophysectomy in the goldfish has been suggested. The main fea-ture of this method is that the pituitary gland is taken out from the opening made by cuttingthrough the anterior parl of the prootic instead of drilling through the parasphenoid bone onthe median oral roof. An incision about 3 mm. long was made through the opercular cavity onthe covering of the oral roof behind the eye. The opercular adductor muscle thus revealed wasexcised. By using a sharp fine scalpel the anterior portion of the prootic and the pterggoidangle of the parasphenoid were cut away. By pushing a little aside the external rectus muscleof the eye and the palatine branch of the Ⅵ eranial nerve, the pituitary gland was exposedand could be sucked away by a fine pipette of suitable size. The operation could be done within 5-7 minutes without doing any injury to the main ves-sels or nerves. Mortality after operation did not exceed 15% of fish operated at 25℃. The operation could be performed either by holding the fish in one hand and doing theoperation with the other or by fixing the fish on a specially designed operation board. Thisboard could also be used in operations other than hypophysectomy in fishes.

Abstract:By analysing the fishing records of the great yellow croaker, Pseudosciacna crocea (Ric-hardson), in spring fishing seasons of 1957-1964, the lesser yellow croaker, Pseudosciaenapolyactis (Bleeker), in the period 1961-1964, in Luzi-yang Fishing Ground, and the ribbon-fish, Tri chiurus haumela (Forskal) in winter fishing season along the coast of Choushan Is lands,the author found that low barometric pressure exerted obvious effect on the catches of thethose important commercial fishes. Several instances illustrating the said relation were brie-fly cited with the help of fish-finding echograms, and dense shoals of the above mentionedspecies under low barometric pressure were also demonstrated. A few points of the results observed may be noted: 1. There is a tendency when the barometric pressure drops down, a much larger dailycatch of these fishes could be anticipated. The catches may rise significantly if the baromet-ric pressure drops down to bolow 1010 milibars, and as long as the low barometric pressurepersists, high catches may sustain. 2. The effect of lower barometric pressure on the catch of the great yellow croakers issimilar to that of the lesser yellow croakers. 3. During the winter fishing season of the ribbon fishes at the Chou shan Fishing Ground,our observation disclosed that, under low barometric pressure of 1021 milibars, the fish shoalswere moving upward towards upper layer of 20 meters, but they started to swim downwardto medium or benthic region as soon as the barometric pressure rose above 1026 milibars. 4. The influence of low barometric pressure is variable in different sea regions.