102 CRETACEOUS GASTROPODA 
once carried out in practice. No smaller number would probably allow of a classi- 
fication of the fossil species, which in neogene and eocene beds are very numerous. 
Some new types will also have to be added. 
The cretaceous representatives are comparatively few, and many of them very 
doubtful as belonging to this sub-family in consequence of their bad preservation. 
The following species have to be transferred to Turricula : Mitra cancellata, Sow. (id. 
et IZ. Cassisiana D’Orb.) ; IL. clathrata, Reuss, (much resembling the new species here 
described as Turricula Arrialoorensis) ; IW. Raemeri, D’Orb.; IL. Leopoliensis, Alth; 
M. nana, Mill.; IL Voitii, Binkh.: to Imbricaria (Conoheliz, Swains.) probably 
belong Mitra conoidea, Math. and MW. Limburgensis, Binkh. and it is, as I stated on 
p- 78, not certain whether this genus, and perhaps Cylindra too, ought not to form 
with Gosaviaa separate sub-family in the Coyzpz. The IW. Cenomanensis and gracilis, 
Guer., and JZ. Requieni and Vignyensis, D’Orb. Ihave not been able to trace. If these 
prove correct, and the Mitra cretacea, Gabb (Pal. Calif. I, 1864, p. 102, Pl. 28, Fig. 
215) with the two Indian species be included, the number of known mzrrrv will be at 
the present not more than fifteen. This small number, as compared with the great 
variety and richness of the recent fauna, is very remarkable. 
Pictet quotes 19 species of JMitra, excluding the two Indian and one American (Mat. 
p. l. Pal. Suisse, 1864, 3me Ser. II, pt. p. 682-684). Of these 19 species the follow- 
ing have however to be most probably excluded: Mit. Murchisont and pyruliformis, 
Miller as Fulguraria and Ficulopsis of the rvozurmv# respectively; IZ. Cassisiana, 
D’Orb. as not different from JZ. cancellata, Sow.; Mitra reticulata, D’Orb. = Cerith. 
reticulatum, Reemer, Pictet and others. Mr. Roemer does not mention anything 
about columellar plaits, and the species must be retained for the present as a Cerithium, 
although it might belong to Chemnitzia or Turbonilla. Of Mit. Zekelii, mtida and 
spinosa from the Alpine Gosau deposits the first two have, I believe, to be retained 
under Fasciolaria and the third as Borsonia, as stated in my Revision of the Gosau- 
eastropoda, p. 87 (Sitz. Akad, Wien, 1865, LIT.) 
I have quoted the asc. gracilis, Zek. (Mitra Zekelii) Pict. et Camp., as 
a Mitra (loc. cit. p. 79), but having examined some very similar forms from 
South India, Iam rather convinced that the species is better placed in the genus 
Fasciolaria, as the insinuations of the ribs correspond with a similar notch of 
the outer lip, which is quite foreign to any known species of the uzrrivz. Besides 
this the shell is much thinner and the canal evidently longer, than even in Turricula 
cancellata, Sow, sp. and others, The Mitra nitida, Pictet and Camp.—Fasciolaria 
nitida, Zek. is identical with the original Fasciolaria elongata, Sow. (Vide my 
Revision. loc. cit. p. 84). One or two new species occur in the Alpme Gosau 
deposits, but they have not yet been described. 
