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A NOTE ON THE EGGS AND EARLY EMBRYONIC 

 DEVELOPMENT OF CYPSILURUS 



BY 



M. RAMASWAMI NAYUDU, B.A. 

 Research Sub-Assistant, Madras Fisheries 



WITH THREE TEXT-FIGURES 



The eggs of the species described by Mr. Hornell in the 

 preceding report when laid are of a glassy transparency with a 

 small opaque white germinal disc in each. They are almost 

 spherical, l'75 to 1'8 mm. in diameter, and are very tough and 

 resilient, rebounding like an indiarubber ball when struck against 

 any hard surface. 



They are attached to floating objects and to one another by 

 means of hyaline filaments issuing from the surface of the egg 

 membrane. These filaments are of three kinds ; first, one single 

 filament, the stoutest and the longest, which is the egg's main 

 anchoring cable ; second, a tuft of 7 to 16 tiny thin short ones 

 exactly at the opposite pole, and third, 4 to 6 medium-sized ones 

 which form side stays. The function of the tuft of tiny filaments 

 is not known as in all the eggs examined they were free and 

 unattached. The egg is very slightly elongated towards the pole 

 from which the stout long filament issues. When the eggs are 

 attached only to one another the main and the side stays are 

 plaited together to form a stout central cord of considerable length, 

 consisting of several thin filaments, from which the eggs project 

 on all sides in the manner of grapes in a bunch in which case the 

 stem of the bunch will represent the stout central cord of the mass 

 of eggs. 



The white disc referred to above is composed of a mass of 

 minute cells which go to form the "germinal disc," indicating 

 thereby that these eggs have already been fertilized ; the position 

 of the disc in the egg does not seem to be constant. A few minute 

 oil globules are scattered about in the yolk. 

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