1905.] 



NATURAL SCIENCES OF PHILADELPHIA. 



215 



Species. 

 H. ferrissi: 

 H. arizonensis: 

 H. bilamellata: 

 H. mearnsi: 



Lamella; present. 



axial, parietal, basal. 



axial, parietal, 



axial, basal. 



axial, 



In H. crossei the axial lamella is so weak as to be readily overlooked. 



Part of the species of this group have the terminal cone short, others 

 having it very long; H. crossei being somewhat intermediate. Other- 

 wise they are very similar externally. They may be grouped thus : 



Cone of the spire short, rapidly tapering. 



Three internal lamellse ....ferrissi Ribbed throughout. 



Two internal lamellse arizonensis ) Median whorls 



crossei \ smoothish. 



cionella 



One internal lamella. 



Ribbed throughout. 



Spire sloiuly tapering. 



mearnsi 



regis | 



chiricahuana J 



cockerelli Median whorls 



smoothish. 



Fig. 1. — Holospira goldfussi. 2. — H. ferrissi. 

 4. — H. chiricahuana. 



3. — //. cionella. 



Holospira ferrissi n. sp. PI. XXVII, figs. 22-25. 



The shell is rimate but imperforate, short and cylindric, rather thin, 

 and very pale brownish-corneous. Whorls 9^ to 11, the first whorl 

 wider than the second, both of them smooth ; all the rest of the whorls 

 are regularly, evenly and closely rib-striate, the riblets as wide as their 



