36 



scythe-shaped projection. This type, as well as the including 

 genus Anchura, differ from the Jurassic genus Alaria, in never 

 having the labial appendage developed during the growth of 

 the shell, so as to be left behind the aperture as projecting 

 spines on the body whorl or spire. It, however, probably in- 

 cludes some of the so-called Alaria. 



628 = Aporrhais decemlirata, Coxrad, Jour. Acad. Nat. Sci. Phila. 

 sec. ser. Ill, 330, xxxiv, 11. 



029 = Rostellaria nebrascensis, Evaxs & Suumard, Proc. Acad. Aug. 

 I85(), l(i-±. 



tJSO = Rostellaria rostrata, Gabb, Jour. Acad. Nat. Sci. IV, 390, Ixviii, 7. 



643 = ISOPLEURA, Meek. Type Rimella ciirvilirata, Conrad, Jour. 



Acad. Nat. Sci. Ill, new series, 1858, 331, 



I cannot think this and the succeeding species congeneric 

 with Rimella rimosa, Sowerby, th.e type of Prof. Agassiz's genus 

 Rimella. 



644 = Chemnitzia Meekiana, Gabb, Jour. Acad. Nat Sci. IV, 1860, 299. 

 646 = PTEROCERELLA, Meek. Type Harpago tippana. Jour. Acad. 



Nat. Sci. Ill, sec. ser. 331, xxxv, 25. 



Shell small, thin ; whorls few, rounded, smooth or subangu- 

 lated ; last one not much enlarged. Lip greatly extended, and 

 ascending the spire, trilobate — the middle lobe much larger and 

 more produced than the others, carinated on the outer side. 



I cannot believe such shells as this should be placed in the 

 same genus with Sirombus chiragra and S. lambis, Linnseus, the 

 types of Ilarpar/o and Ptcrocera ; nor is it probable that any of 

 our Cretaceous or older species, usiaally referred to Pterocera, 

 really belong to that genus as properly restricted. This type 

 should probably be placed in the Aporrhaidae, on p. 19 of the 

 List, instead of in the Strombidas. 



651 = CHEMNITZIA, Conrad, 1860 (not D'Orbigjy, 1839). Mr. Con- 

 rad proposes to retain this name for a group of Cretaceous 

 shells which he ranges as a subgenus under Tnrhonilla, Risso. 

 He does not say which species he regards as the type of the 

 group, though his description was evidently written from his 

 C. laqueata and C. melanopsis ; consequently I have regarded 

 these as typical, and the others as doubtful forms. 



658 = Scalaria texana, Roemer, Kreid. Vou. Tex. 1852, IV, fig. 11, a, b. 



662 = Scalaria Forshayii, Siiumard, Proc. Bost. Soc. Nat. Hist. Sept. 

 18(51, 195. 



668 = Natica acutispira, Siiumard, Trans. St. Louis Acad. I, 597. 



689 == Volutilithes bella, Gabb, Jour. Acad. Nat. Sci. IV, sec. ser. 300, 



xlviii, 7. 



690 = Volutilithes biplicata, Gabb, ib. 6. 



691 = Volutilithes Conradi, Gabb, ib. 10. 



692 = Volutilithes nasuta, Gabb, ib. 9. 



