240 CRETACEOUS PELECYPODA 



favour of his classification of this problematic fossil. The upper valve, says Gahb, 

 has not yet been observed. 



In some respects Tamiosoma recalls the organisation of the peculiar Hippurite 

 from Jamaica, called by Woodward Barrettia. 



List of species of HippuritiDjE. 



Lists of most of the species of this family have heen lately published hy Pictet and 

 Campiche in the " Mat. p. 1. Pal. Suisse", S""" ser., 4""= partie, p. 10, &c. The f^eneiic and 

 most of the specific identifications have been accepted according to the elaborate papers of Mr. Bayle, 

 published in the Bull. Soc. Geol. de France. I shall here only quote the names of the species, 

 addino- a few which are not included in that last comprehensive list. With reference to the generic 

 determinations of some of the species of Radiolites and Spharulites I have already expressed some 

 doubt, and I shall note them in detail further on, though for the present these notes can only be 

 accepted as suggestions, as I have no sufficient materials for comparison. But it seems to me that 

 the discrimination of the two last named genera has not been fully carried out, and that the 

 occasional presence of the so-called cartilage hinge-ribs in the attached valve of Radiolites has given 

 rise to pronouncing the species to belong to Spharulites, when only one of those ribs was observable. 



1.4. — Radiolites canalicuhita, d'Orb., sp., cor?iu-pas(oris, Desm., st^., a7iffulosa, d'Orb., sp., 

 lumbricalis, d'Orb., (the last is probably a SpheerulitesJ . 



b.—Rad. acuticostata, d'Orb. This is a very peculiar costate form, having the free 

 valve also strono-ly ribbed and the apex sub-central ; it possibly indicates a special section of 



Radiolites. 



6-15.— Rad. excavata, d'Orb., i^iffens, Desm., sp., fssicostata, d'Orb., Roj/ava, A'Drh., 

 Mauldei, Coq., crateriformis,!) esm., sp., Jouanneli, Desm., Bounioni, I) Qsm., tindulata, Gein., 



Saxonia, Rom., sp. 



lg.18. Jt_ Trigeri, Bayle, Lapeyrousei, Gold., (apparently as distinct from radiosa), and 



Ciplyana, Ryck., are quoted, besides some others by Bosquet from the Mastricht beds in S taring's 

 Bodem van Nederland, ii deel. 



l9.—Biradiolites Rozowii, Fisch., is described by Eichwald in his Leth. Ross., lO-Mivr., 

 1867, p. 357. It appears to be a Radiolites, though the existence of two furrows is mentioned 

 in both valves. It was originally described by Fischer as Cibicides Rozowii from upper creta- 

 ceous beds at the river Ratowka near Vereya in Govt. Moscou. 



Eichwald also mentions Enargetes of Fischer, which may be a Radiolile, and another 

 problematic form which Fischer called Tripodetes. 



20. — Rad. Nicaisi, Coq., is from Algiers. 



21-25. Rad. Aimesii, Tuom., JusfinensiSj Rom., lamellosa ^- Ormoudii, Tuom., and 



R. Tuomei/ana, Gabb, are quoted from North America in Meek's Clieck-list of cret. foss., Smith. 

 Misc. Coll., No. 177, p. 5. 



SphcBruliies (vide Piet. and Camp., 1. cit., p. 50). 



^Q.^^.—Sph. Blumenbackii,?>ivL(iL., Marticensis, A' Oxh., sp., errafica, Pict. et Camp., para- 

 doxa, P. and C, foliacea, Lamck., Fleuriansi, d'Orb., sp., triangularis, d'Orb., sp., poli/conihtes, 

 d'Orb., sp. (non pohjconites), sutjdilatata, elliptica, and Germatii, Gein., sp., falcata, Reuss., 

 Mortoni, Mant., (is to all appearance a RadiolitesJ, Ponsiana, d'Arch., Beaumonti, Bayle, radiosa, 

 d'Orb., sp., Sauvagesi, d'Hombres Fir., sp., Nouleti, 'Ra.yU, squatnosa, <k' 0th., angeiodes, V\coi 

 d. 1. Peir. 



46-48. — Sp/i. 3Iartini,Failetlei &nd sinuata oi d'Oihigny have in external appearance quite 

 the form of Radiolites. 



