GODWIN-AUSTEN: ON MACBOCIILAMYS FROM MAURITIUS. 321 



has a well-developed overhanging lobe (Fig. v). The shell-lobes 

 (Figs. VI, vii) are well developed, both long and tongue-like, the left 

 dorsal in two parts, the posterior one being small. The form of the 

 shell-lobes distinguishes this at once from sp. A. 



The third species sent me by Mr. Ponsonby may possibly belong to 

 the same genus, yet it might turn out to be some other ; the interest 

 will be increased if it should be a Macrochlamys, and leave less 

 possibility of all three being imported species. It becomes now very 

 important to know the exact localities in the island where these 

 land shells were collected. If from the neighbourhood of town 

 gardens, they may easily have been brought from abroad, particularly 

 from botanical gardens in India, supplying plants to the Mauritius. 

 If found in remnants of the old forests, far away from the coast, we 

 should feel more confident they were indigenous forms. On this 

 point I hope to hear more from Monsieur Dupont, and perhaps receive 

 other material. 



Geoffrey Nevill, in a paper (" Note sur deux coquilles terrestres, 

 decrites par Deshayes comme recueillies a Pondichery par M. Belanger " : 

 tTourn. Conchyl., xxvi, 1878, p. 59) which treats of two species, 

 seniifiisca, Desh., and Woodiana, Pfr., says the former is excessively 

 abundant in the vicinity of the town of Port Louis. He was evidently 

 writing on one of the three species lately sent home. Further on he 

 says : " D'apres le souvenir que j'ai de I'animal, il se rapproche 

 plutot du type des Macrochlamys que de celui des Eotida, mais je 

 puis, pourtant, me tromper, sous ce rapport." Semper has described 

 two species from the adjacent island of Bourbon, viz. coelatura and 

 rufa, and places them in his genus Rotula. The anatomy' of this genus 

 differs in many important particulars fi'om that of Macrochlamys, and 

 shows it to be widely different. On the receipt of the Mauritian shells, 

 I fully expected to find them species of Rotula. 



The presence of true Macrochlamys in an island of the Indian Ocean, 

 so far away to the south as the Mascarene Islands, is of extreme 

 interest, provided we can feel clear it is an indigenous genus. Its 

 presence would have a most important bearing on that very absorbing 

 question, the ancient continuity of the Indian peninsula southward 

 to Madagascar and Africa. 



EXPLANATION OF PLATE XVIII. 

 Figs, i-vii. Macrochlamys spp. ; Mauritius. 



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