INVERTEBRATES. 377 



Genus LOXONEMA, Phillips, 1841. 



. (Palaeozoic Fossils, p. 98.) 



We doubt the propriety of referring such forms as we here range under 

 the name Loxonema, to the recent genus Turbonilla, Risso (= Chemnitzia, 

 d'Orbigny), since they are generally not only much larger shells, but differ in 

 not having, so far as we have been able to see, the apex of the spire reversed, 

 as in the species upon which the genus Turbonilla was founded. We therefore 

 agree with those who prefer to retain Phillips's name, Loxonema, for these 

 older fossil species. It is, however, we think, generally made to include species 

 belonging to other allied, but distinct types: L. ? compacta, L.f obtusa, etc., of 

 Hall (Palaeontology of New York, vol. iii, pi. 54), for instance, belonging 

 apparently to Rcemer's genus Michelia. 



Loxonema scitula, M. and W. 



PI. 31, figs. 10a, 10 b, 10c. 



Loxonema scitula, Meek and Worthen, October, 1860. Proceedings Acad. Nat. Sci., 

 Philad., p. 464. 



Shell small, elongate-conical ; spire elevated and regularly 

 tapering; volutions eight to eight and a-half, very slightly 

 convex, increasing gradually in size, last one rounded and not 

 produced below; suture moderately well defined; aperture 

 obliquely ovate, acutely angular above and rounded below. 

 Surface ornamented by distinct, regularly disposed vertical 

 folds or costae, about fourteen of which occupy each turn; folds 

 equaling the depressions between, and on the last turn becoming 

 suddenly obsolete below the middle; no lines of growth visible. 

 Length, 0.23 inch; breadth, 0.10 inch; length of aperture, 

 0.07 inch ; breadth of ditto, 0.04 inch. Apical angle regular, 

 divergence 27°. 



Locality and position: Lower Coal Measures, Hodge's creek, Macoupin Co., 

 Illinois.* 



* In first publishing this species, Springfield was by mistake given as the locality. 

 48 Sept. 20, 1806. 



