Zoot.— Vol. I.] RITTER—DIEMYCTYLUS TOROSUS. 99 



envelop so characteristic of amphibian eggs. Usually the 

 gelatin of from ten to twenty-five eggs is run together so as 

 to make practically a common mass. 



When first deposited the gelatin is semifluid and very 

 viscid, but after being immersed in the water for a short 

 time it both swells up and hardens; so that ultimately the 

 masses are of considerable size — 2 cm. in diameter being 

 about the average — and are quite firm, their consistency be- 

 coming considerably greater than that of the firmest fruit 

 jelly. 



For several hours after deposition a well defined layer of 

 gelatin immediately surrounding the egg is somewhat less 

 transparent than the rest of the mass. This is seen in 

 fig. 11, representing a bunch in which the clearing and 

 liquefaction of this portion, both of which take place at a 

 later time, was not yet complete. It is of historic interest 

 that Spallanzani supposed this inner capsule to be " nothing 

 else than the amnios full of liquor." 



There is thus seen to be a striking difference between 

 our species of Diemyctylus and its relatives, D. viridescens, 

 of eastern North America, and the European Tritons (for 

 information concerning egg-laying by T. cristalus in par- 

 ticular, see Wood ['71] and Brehm ['78]), in the manner 

 of depositing the eggs. It is well known that these species 

 lay their eggs one in a place. It is further given as a 

 characteristic of them that the eggs are more or less se- 

 creted and protected by the leaves of water plants among 

 and upon which they are placed. For the egg-laying 

 habits of D. viridescens see particularly Jordan ('93) and 

 Gage ('91). 



But the difference between the two methods is not in 

 reality very great after all. In D. torosus the long, much 

 coiled oviduct becomes filled with ova, always, however, in 

 a single row, before egg-laying begins; and their being 

 deposited in masses is due to the fact that they cling so 

 closely to one another by the viscid jelly that they cannot 

 be readily separated as they leave the cloaca. Of course 

 the remaining of the mother in the same position while a 



