H 



Erwiu H. Barbour. 



Daimonelix Circuinaxilis, gen. ct sp. nov. 



This is the largest species of the genus as far as known, 

 and the first I obtained. It is characterized by a perpendicu- 

 lar axis, supporting a spiral, and having a greatly enlarged, 

 obliquely ascending, underground portion. The axis is reg- 

 ular and often sharply defined ; the spiral, strongly marked 



and wrinkled, with trans- 

 verse ridges on the supe- 

 rior surface ; smooth, flat, 

 or square-cut on the infe- 

 rior surface. (See Figs. 27, 

 28, 29, Plate V.) 



The species is further 

 characterized by an intri- 

 cate net-work of silicious 

 tubes, not unlike a mass 

 of tangled moss, particu- 

 larly conspicuous on the 

 underground or transverse 

 portion (see Plate III., Fig. 

 21) and throughout the 

 spiral. For the foregoing 

 characters, see Figs. 13 to 

 17, Plate I. ; Plates II. and 

 III. ; also compare Figs. 2^, 

 28, 29, Plate V. 



Figs. 14, 15, and 16, 

 Plate I., give three aspects 

 (viz. opposite sides and a back view), one section, and a quarry 

 scene of the first specimen I secured. We dug out nearly 

 seven feet of the underground portion. Finding it impossible 

 to go further, and not reaching the end, we broke off about 

 three feet of it, leaving the rest in the bank. This portion, 

 temporarily abandoned, was secured immediately on entering 

 the field with the Morrill expedition. It measured five feet 



314 



Fig. 10. — A noticeably regular specimen of 

 Daimonelix circumaxilis. Sketched from 

 a specimen in the collection of Mr. C. E. 

 Holmes. 



