NO. 1431. • BREEDING HABITS AND EGG OF PIPEFISH— GUDGEE. 465 



the following- nio-ht. One of these, stripped the second time, died after 

 taking on a third lot. When the egg.s have been in the pouch thirty- 

 six or forty-eight hours they become tirmly fastened to it both at top 

 and l)ottom, so that it becomes necessary to kill the fish and then cut 

 away the flaps of skin before one can extract the eggs. 



The fishes vary in size. The extremes in egg-bearing males of xV. 

 -florula' I have found to be 4.5 to 8.1> inches, and in females 3 to S.4 

 inches. As a g'eneral rule, however, the females are somewhat the 

 larger. 



THE SEGMENTATION OF THE EGG OF THE PIPEFISH— 

 SIPHOSTOMA FLORIDiE. 



I. THE OVARIAN EGG. 



The ripe ego;^ of this fish is of fairly good size, having a diameter of 

 about 1 mm. It possesses a thin transparent membrane or shell, 

 which, under the one-tw^elfth homogeneous oil immersion lens, shows 

 no structure in sections, but in surface views presents, when stained 

 lightly with heemalum, a notably punctate appearance. These mem- 

 branes were generally removed after killing the eggs, but, if left on 

 the eggs, do not get very hard and oft'er no obstruction to embedding 

 and sectioning processes. The eggs are formed in ovaries which, 

 viewed from without, present the ordinaiy Y-shaped structure common 

 to the Teleosts. These ovaries are two tubular organs situated in the 

 posterior dorsal portion of the body cavity, and are confluent behind 

 to form the short oviduct which opens on the posterior lip of the anal 

 aperture. 



However, when one of the ovaries is sectioned, a ver}^ interesting 

 structure is revealed. Running lengthwise throughout the whole 

 extent of the ovary is a raphe situated about two-thirds of the dis- 

 tance from one wall. From this eggs are budded off in succession to 

 foi-m a spiral of eggs which surrounds the raphe, the outermost Qgg 

 being the oldest and largest. As this Qgg ripens it markedly increases 

 in size and crowds the other eggs together with the raphe closely to 

 one side of the tube. In the ovaries of older and larger flshes, two or 

 three eggs may ripen side by side and then the raphe and its 3'oung 

 eggs are very much crowded and contorted. As the eggs become ripe 

 they enormously distend the ovaries both in diameter and length — in 

 length until they frequently extend forward to the region of the 

 stomach. At this time females ready to spawn are noticea))le for 

 their greath' distended abdomens. 



The 3"oung eggs, as first pointed out ])y Cunningham (1S!)7), have 

 large nuclei with several nucleoli, but in the older ovarian eggs the 

 germinal vesicle is not so apparent. The grown egg^ still attached 

 in the ovary, is surrounded by a layer of peripheral oil drops. This 

 same structure persists in the eggs after extrusion, so that the ger- 



