214 M. E. Claparbde on a new Genus 



6. Oliva puhhra^ Marrat. 



Shell fusiform, rather narrow ; spire conical, whorls slightly 

 flattened ; suture canaliculate ; pale cream-coloured, with 

 brown festoons below the suture ; body-whorl with irregular 

 brown longitudinal flames, spotted above the white basal 

 band ; columella slightly granular, with a single fold at the 

 base. 

 Among some shells from California; but the locality is 



doubtful. A small shell, not larger than 0, oryza^ Lam. 



XXIII. — On a new Genus of Gastrotrichous Rotatoria. 

 By E. Claparede*. 



The genera ChcetonotuSj Ehrb,, and Ichthydium^ Ehrb., have 

 hitherto occupied only an uncertain place in the zoological 

 system. M. Ehrenberg joined them to Ptygura and Gleno- 

 j)hora to form a family of Kotatoria ; Dujardin considered 

 them to belong to the Infusoria ; M. Yogt classes them in a 

 general way among the Vermes ; M. Schmarda makes them 

 almost Annelides ; M. Ehlers even approximates them to the 

 Nematoida. The opinion most generally accredited is that 

 which regards them as Turbellaria. M. Max Schultze was 

 the first to develope this opinion when he made known, under 

 the name of Turhanella^j a new genus belonging to the same 

 group. The two authors who have most carefully studied 

 these interesting animals of late are Mr. Gosse % and M. Mecz- 

 nikow §. 



The former, in making known several new species, avoids 

 pronouncing an opinion on the natural position to be assigned 

 to the family Chaetonotides (Hairy-backed animalcules, as he 

 calls them). It was, indeed, very difficult for him to form a 

 judgment, on account of the unfortunate union with this family 

 of two dissimilar genera, namely, Taphrocamjpa^ Gosse, and 

 EcMnodereSj T)u]. Now the TaphrocampcB are, as I have 

 already demonstrated, true Rotatoria. As to Echinoderesj it 

 has no affinities with either the Rotatoria or the Turbellaria. 

 The mistake of Mr. Gosse with regard to them is easily ex- 



* Translated from the ' Annales des Sciences Natiirelles/ 5« s^r. tome 

 viii. pp. 16-23. 



. t Beitrage zur Naturgeschichte der Turbellarien, von Dr. Max Sigis- 

 mond Schultze, (Greifswald) p. 69. 



\ " The Natural History of the Hairy-backed Animalcules " (Intellec- 

 tual ObseiTer, 1864, pp. 307-406). 



§ " Ueber ChcBtonotus und Icthi/diu7n^ mid eine ncue verwandte Gat- 

 tung Turhanella,'' Miiller's Archiv, 1853, p. 241. 



