70 HOLOSPIRA. 



forms. The central and lateral teeth have single, stout, conic 

 cusps. The transition to marginals is made by the gradual 

 development of an ectocone, at first small and simple, and in 

 the usual position. The outer marginal teeth are short, wide 

 and usually have both cusps bifid, or the outermost ones may 

 be irregularly cusped. The count of teeth is less than in typ- 

 ical Holospira, as follows: H. (Bostrichocentrum) tryoni 

 13.7.1.7.13=41; H. (B.) pilsbryi (pi. 50, fig. 5) 13.6.1.6.13 

 = 39; H. (Haplocion) minima 17.6.1.6.17=47; H. (Meta- 

 stoma) roemeri 13.7.1.7.13=41; H. (Ccelostemma) dalli 

 13.8.1.8.13 = 43; H. (C.) elizabetha has 8 or 9 unicuspid 

 laterals. 



In H. goldfussi, Strebel & Pfeffer found a type of radula 

 quite unlike those examined by Fischer or myself, and differ- 

 ing widely from what Binney figured for the same species. 

 They describe the central and lateral teeth as with ectocones 

 wholly separated from the cusp, and concrescent with the 

 basal-plate of the next older tooth. The main cusps are very 

 short and broad, etc. This differs so radically from what has 

 been observed in other species that I am compelled to believe 

 that some mistake in the identity of the radula was made. 

 Indeed I believe that Strebel got the radulae of Epirobia 

 berendti and Holospira goldfussi transposed, and figured the 

 one for the other. The forms of the individual teeth and the 

 formula given for a transverse row point significantly to this 

 conclusion. 



The genital system of H. goldfussi (pi. 19, fig. 52) has been 

 examined by Strebel & Pfeffer; of H. nelsoni (pi. 27, figs. 

 33, 34), H. (Metastoma) roemeri (pi. 27, fig. 36), H. (Ccelo- 

 stemma) dalli (pi. 27, fig. 35) by myself. In all of them there 

 is an atrium of moderate length ; the penis is short, with a very 

 long vas deferens; the retractor muscle (p. r.) being inserted 

 at or just beyond the slightly swollen penis, and proximally 

 attached to the floor of the lung, as usual. In H. nelsoni there 

 are internal folds in the penis, showing through. There are 

 no accessory organs. The spermatheca and oviduct are sepa- 

 rate to the atrium in the species I have opened, but in H. gold- 

 fussi, Strebel figures a capacious vagina. The oviduct is ex- 



