Dr. J. E, Gray on the Land Pulmoniferous Mollusca. 267 



Fig. 14. Peltogaster sulcatus ; the animal seen from the left side : a, the 

 organ of adhesion ; b, the anterior orifice of the body. 



Fig. 15. Peltogaster microstoma ; the animal seen from the left side : 

 a, the organ of adhesion ; b, the anterior orifice of the body. 



Fig. 16. The larva of P. microstoma, at the point of being hatched, seen 

 from above. 



Fig. 17. The larva of a Pachybdella (after Cavolini). 



XXXV. — On the Arrangement of the Land Pulmoniferous Mol- 

 lusca into Families. By Dr. J. E. Gray, F.R.S., V.P.Z.S. 



The opportunity of examining the genus Aneitea, and the addi- 

 tional information obtained by the publication of the anatomy 

 of it by Dr. Macdonald, and of that of Janella by Mr. Knight, 

 has induced me to reconsider the subject of the arrangement 

 of the terrestrial Pulmonata or Pulmonata geophila, given in the 

 Catalogue of Pulmonata, or Air-breathing Mollusca, in the British 

 Museum, published in the year 1855. 



I would suggest, for the arrangement given at page 2 of that 

 Catalogue, the following : — 



1. Pulmonata geophila. Eyes at the apex of an elongated 

 cylindrical peduncle. Tentacles cylindrical, shorter and lower 

 down than the eye-peduncle, sometimes very small or wanting. 

 Operculum none (except in young Cryptella ?). Terrestrial. 



A. Headj eye-peduncle, and tentacles retractile under the skin* 



Sect. 1. Vermtvora. Buccal mass very large, elongate, pro- 

 jectile like a proboscis. Jaw none ; teeth numerous, slender, 

 conical, distant. Mantle well defined. Subterraneous; carni- 

 vorous, or worm-eating. 



* The spiral part of the body near the middle of the back. Head 

 without any lateral grooves from the front of the mantle to the 

 outer edge of the eye-peduncles. 



1. OleacinidjE. The tentacles cylindrical, simple ; the labial 

 tentacles elongate, produced, flat, angularly bent. Shell oblong, 

 spiral ; the outer lip thin, sinuous. Oleacina. 



It is to be observed that some Helicinidce have shells so like 

 Oleacina(&s, for example, Achatina folliculus), that it is impossible 

 to distinguish them from the shells of true Oleacince; yet Moquin- 

 Tandon has figured the animal and the jaws of them, showing their 

 Helicine character and phytophagous habit (see t. 20 & 22), and 

 the animal and jaws have been observed in several other species 

 that have been referred to this genus on account of the form of 

 shelL The genus Halea, which differs from Oleacina only in 



18* 



