MOLLUSCA OF INDIA. 57 



Mr. Collinge and myself considered was an oversight. These very 

 thin memhranaceous shells may easily escape notice ; and further, 

 in all the species from the Indian region a shell is always present, 

 however membranaceous and small in size it may have become. 



Genus Parmarion, Fischer, 1855. 



[Actes de la Soc. Linn, de Bordeaux, ser. 2, vol. x. 

 p. 389, pi. XX.] 



Original description : — " Bouclier adherant au corps par une faible 

 partie de son bord, etale en avant en un grand lobe libre, entourant 

 sur les cotes et en arriere presque toute la coquille, perce d'une 

 ouverture dorsale, plus ou moins large, au-dessous de laquelle se 

 montre le test. Sole du pied tripartie ; pied tronque en arriere, 

 pourvue d'un pore muqueux ; masse visceralo bombee en arriere et 

 bien separee du pied. Dents marginales bicuspidees. 



" Coquille interne ealcaire, mince, ovalaire, legerement bombe'e, 

 couverte d'un epidermc lisse qui la debord sur les cotes et en arriere 

 et qui enveloppe la masse viscerale." 



In the ' Manuel de Conchyliologie ' (1887), from which the above is 

 copied, Fischer makes the type Limax prohlematicus, F6v.==P. pujnl- 

 laris, Humbert, of Ceylon, and goes on to say : " many species are 

 described under the generic name of Girasia, Gray, 1855 ; but this 

 genus, badly defined by its author, has been created for a medley of 

 ParmaceUa, Urocyclns, or Parmarion. The true Parmarion would be 

 Asiatic." Fortunately, Gray most clearly indicated his type, G. hoolceri, 

 as I have recorded before (Vol. I. Part VI. p. 216 ). When we consider 

 the knowledge of his day, and the method in which a group like the 

 slugs were approached, and the ideas on relationship which then 

 prevailed, it is of minor importance what species were included under 

 any given generic title, or whether they all corresponded with the 

 type ; descriptions were then usually confined to the external features 

 alone, and even Fischer's description of Parmarion might be made 

 to apply to many very different slugs, looked at superficially, but is 

 not sufficient for the way in which they should be studied and 

 their affinities worked out. 



Simroth treats this genus with great care and detail, quoting the 

 original and then Tryon's description, which also does not go beyond 

 external characters. Fi'om Simroth's own description we first begin 

 to understand what Parmarion of the island of Java really is, and 

 that it differs essentially from Girasia (see his drawings of the 

 anatomy of P. jjupillaris., pi. viii. figs. 16 & 17 ; also my copy of 

 Seraper's rendering of the same on PI. LXXIV. figs. 6, 6 a). I 

 cannot do better than quote his generic description of Parmarion 

 and his new subgenus Microparmarion, type M. strubelU^ Simroth, 

 also from Java : — 



Parmarion. — " Die Mantelkante springt stark vor. Die Schale 

 ist einer zarte Kalkplatte, ahnlich wie bei Limax, mit einer kraftigen 

 glanzenden Epidermis, die sichrects und links iiber den Hand, 



