Say el ery ANY AE O MY -"O:8 MP EEO 
TN -Dil CC UOrS; “Grielin. 
By H. J. FLeure, Professor of Zoology, University College of 
Wales, Aberystwyth. 
(Plates xxvili-xxxii). 
I.—INTRODUCTORY. 
Through the kindness of the authorities of the Indian Museum 
of Natural History, and of Dr. J. Travis Jenkins, two specimens of 
Melo indicus, Gmelin, were forwarded to me for examination. 
The identification was made by Mr. Preston and confirmed by 
Mr. E. A. Smith. Melo is a genus, or subgenus, in the family 
Volutidae, belonging to the Stenoglossa Rhachiglossa in Bouvier’s 
classification of the Monotocard Gastropods. 
Bouvier makes the following the chief characteristics of the 
RHACHIGLOSSA :— 
I. The central tooth of the radula is nearly always well de- 
veloped and the radular formula is not above I. I. r. 
2. The special unpaired gland of the oesophagus is well 
developed, but its duct only rarely traverses the nerve 
collari(pl xxxne.- 6; Unp.Gir). 
3. The supra-intestinal ganglion approaches the right pleural 
ganglion (pl. xxxii, fig. 21, R. Pl. G. and Sp. Int. G.). 
4. The visceral ganglion is subdivided (pl. xxxii, fig. 21, V 
and V3). 
These characters seem to mark them out among the STENo- 
GLOSSA, which are characterized by Bouvier as follows :— 
I. Radular formula 1. 1. 1., often reduced in various ways. 
2. A retractile proboscis (pls. xxviii and xxix, figs. I—a, 
Pr.), a well-developed pallial siphon (S), a siphonosto- 
matous shell, a large and bipectinate osphradium 
(Osph.), a penis. Accessory tubular buccal glands 
(pl. xxx, fig.6, T. B. G.) may occur, there is one 
pair in Halia, one pair with ducts uniting in Volu- 
tidae, etc., none are found in Buccinidae. 
3. A pair of racemose buccal glands with ducts which do not 
traverse the nerve collar (pl. xxx, fig.6, R. B. G.). 
4. A special unpaired gland of the oesophagus in many 
forms (pl. xxx, fig. 6, Unp. Gl.). 
5. A highly concentrated nervous system without labial 
commissure or pedal cords. The ganglia of the re- 
duced buccal mass near the cerebrals. Zygoneury 
