7178 Batrachians and Fishes. 



probably to be discharged in three successive years ; the mature eggs 

 of a Jara-bakka eighteen inches long measure three-fourths of an inch 

 in diameter, those of the second zone one-fourth, and those of the 

 third, or very minute, about one-sixteenth of an inch. 



A careful examination of eight specimens of Njinge-njinge, about 

 nine inches long, gave the following results. 



The eggs in all instances were carried in the mouths of the males. 

 This protection, or gestation of the eggs by the males, corresponds 

 with what has been long noticed with regard to other fishes, as for 

 example Syngnathus, where the marsupial pouch for the eggs or 

 young is found in the males only ; and Gasterosteus, where the male 

 constructs the nest, and protects the eggs, during incubation, from 

 4,he voracity of the females. 



In some individuals the eggs had been recently laid, in others they 

 were hatched, and the fcetus had grown at the expense of some other 

 food than that derived from the yelk, as this last was not proportion- 

 ally diminished in size, and the fcetus weighed more than the unde- 

 veloped egg. The number of eggs contained in the mouth was 

 between twenty and thirty. The mouth and branchial cavities were 

 very much distended, rounding out and distorting the whole hyoid 

 and branchiostegal region. Some of the eggs even partially protruded 

 from the month. The ova were not bruised or torn as if they had 

 been bitten, or forcibly held by the teeth. In many instances the 

 fcetuses were still alive, though the parent had been dead for many 

 hours. 



No young or eggs were found in the stomach, although the mouth 

 was crammed to its fullest capacity. 



The above observations apply to Njinge-njinge. With regard to 

 Jara-bakka, I had but few opportunities for dissection, but in several 

 instances the same conditions of the eggs were noticed as above; and 

 in one instance, besides some nearly mature fcetuses contained in the 

 mouth, two or three were squeezed apparently from the stomach, but 

 not bearing any marks of violence or of the action of the gastric fluid. 

 It is probable that these found their way into that last cavity after 

 death, in consequence of the relaxation of the sphincter which sepa- 

 rates the cavities of the mouth and stomach. These facts lead to a 

 conclusion that this is a mouth-gestation, as the eggs are found there 

 in all stages of development, and even for some time after they are 

 hatched. 



The question will be very naturally asked, how, under such cir- 

 cumstances, these fishes are able to secure and swallow their food. I 



