194 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



further opportunity to carry my researches any farther. The materia] 

 which was obtained was however of such an interesting- character that 

 I immediately made a number of camera lucida sketches and a few 

 notes, which I now reproduce. 



The eggs being taken at night, renders it possible that the species is 

 a nocturnal spawner, while the singular threads or filaments may 

 be the means by which the parent fish is enabled to suspend its ova to 

 some fixed support in the water as they are emitted from the oviduct. 

 This might be accomplished by the female while the eggs were expelled 

 by simply passing her body over the stems or leaves of marine plants 

 in her vicinity. This affords an explanation of the remarkable threads 

 which are attached to and at first encircle the eggs. We cannot escape 

 the conclusion, at any rate, that these threads are of the nature of a 

 protective contrivance either to suspend the eggs to foreign objects or 

 else to entangle them together in masses ; such as we find to be the case 

 with the eggs of the silver-gar, where the filaments are, however, scat- 

 tered over the whole surface of the egg. Tbe eggs of the silver-gar are, 

 moreover, actually found suspended in masses in the meshes of the 

 pound-nets in which the adult females have been entrapped, but whether 

 the fish themselves have been the means of suspending them there is 

 uncertain. Possibly currents of water may waft them into the meshes 

 of the nets, but this is to some extent improbable from the fact that 

 the ova of the gar are much heavier than sea-water and immediately 

 sink to the bottom. The eggs of Menidia notata are also heavier than 

 water, and it is therefore very possible, as previously suggested, that this 

 form, too, may, when spawning, avail itself of the threads on its ova to 

 suspend them by, so as to keep them out of the mud and prevent them 

 from being smothered and killed. The filaments of adjacent eggs in 

 the gar have a tendency to twist spontaneously around each other, so 

 that great masses are often formed in this manner and held together 

 entirely by the tough fibers or filaments which are attached to the egg 

 membrane. The same is true of the eggs of Menidia, but in this genus 

 the eggs are not deposited in such numbers, because the ovary of a full- 

 grown female would probably not yield more than 300 eggs during a 

 single spawning season, while that of the female silver-gar would yield 

 as many as 800 to 1,000 ova. 



The mature eggs of Menidia notata measure about aline in diameter, 

 and as shown in Fig. 1, in the accompanying cut, are covered with a 

 thick, strong egg-membrane, z. When first taken from the parent fish, 

 the germinal matter of the ovum is spread mainly over the surface of 

 the vitellus, and in the latter a number of highly refringent oil globules 

 of various sizes are embedded, as shown in Figs. 1, 3, and 4. In the 

 space of ten hours the batch of ova studied by the writer had developed 

 the germinal disk y independently of impregnation. 



Probably the most striking peculiarity about the ova of Menidia is the 

 garniture of threads which are attached to one pole of the egg, covering 



