34 EIGENMANN AND DENNY. [VOL. II. 



A preliminary note by the present authors (Proc. Ind. Acad. 

 Set., 1898, p. 252, 1899) completes the list of papers dealing 

 with this species. 



In the spring of 1897 Dr. Eigenmann visited Rock House 

 Cave and secured a number of larvae, which Dr. Stejneger pro- 

 nounced the larvae of Typhlotriton. Later Mr. E. A. Schultze 

 informed him that he had seen this salamander in the under- 

 ground passage to Bloncli's Throne Room in Marble Cave, 

 Stone County, Missouri. In September of 1898 he visited this 

 cave and secured four adults and three larvae of Typhlotriton. 

 A large number of the larvae were obtained from Rock House 

 Cave a few days later. Those from the latter cave were found 

 under loose stones and gravel in the rivulet at the mouth of 

 the cave. They had been exposed to the light. It is scarcely 

 supposable that those from Marble Cave had ever been affected 

 by the light. In the caves both larvae and adults are found 

 under the stones, the old ones in and out of the water. 

 Occasionally one is seen lying on the bottom of a pool. 



In the aquarium the larvae creep into or under anything 

 available ; a glass tube serves as a " hiding " place. The 

 rubber tube admitting water to the aquarium is sometimes 

 occupied by several during a temporary cessation of the flow 

 of water. A wire screen sloping from the bottom of the 

 aquarium formed the most popular collecting place for the 

 larvae. They collected beneath this, although it was no pro- 

 tection from the light. From these observations it seems 

 probable that stereotropism rather than negative heliotropism 

 accounts for the presence of this species in the caves, and that 

 this reaction has been retained after the long stay of the species 

 in caves necessary to account for the changes in its eyes. 



The eyes of the larvae when examined from the surface 

 appear perfectly normal, but they are little used in distin- 

 guishing objects. When hungry they will strike at a stick 

 held in the hand as they would at food. A stick lying at the 

 bottom of the aquarium undisturbed is not molested. They 

 strike at a worm when touched by it, or when it approaches 

 close enough for its motion to be perceived. 



In the larvae up to 90 mm. long the skin passes over the 



