rm 
IL 
Shell a thin, flat, almost eircular ealcareous plate, witlı dark amber or horn- 
eoloured periostracum, the membranaceous border overlapping the edoe of the plate. No 
trace of an apical whorl. 
Major diameter 11,5 mm, minor diameter 6,5 mm; actual size of calcareous plate. 
74,5 mm. 
Hab. Mindoro. 5000 feet. (J. WHITEHEAD). Type in collection of British 
Museum. 
Anatomy. 
Generative Organs. — There is a wide sac-like vestibule into which all the 
organs open. The penis is a thick muscular organ with a narrow lumen, attached to its 
distal end. is a short broad retractor muscle. The vas deferens is a long narrow tube, 
it enters the penis at the proximal end, just before the connection with the penis, the 
tube widens and forms a short, wide tube (Pl. VIII, fig. 12). There is a short recepta- 
eular duet with a somewhat ovoid receptaculum seminis, which shows a slieht constrietion 
distally. The receptaculum seminis is a little less in length than the penis. The vagina 
gives place below to the wide-sac-like and irregular shaped free oviduct, on the outer 
side of which there is a large ovoid expansion (Pl. VIII, fie. 12d). The common duet 
calis for no special mention, beyond that the prestatic portion stands out as a very distinet 
tube. Only having a single specimen, it was desirable that the whole of the visceral 
mass should be left undisturbed, the albumen gland and the hermaphrodite gland were 
therefore not dissected out. The dart-sac (Pl. VIH, fig. 12, d.s.) is a large and con- 
spicuous body, nearly twice the lengtlı of the penis. Externally it is covered by a loose 
sheath composed mainly of plain muscle fibres. It may be divided into two parts, the 
solid distal portion, to the end of which is a strong retractor muscle, and a proximal 
folded upon itself. The fold is not apparent to the naked eye or indeed with a low 
power lens, but on striping otf the muscular sheath it is readily distinguished (Pl. VII, 
fig. 13). The dart is a small, simple, calcareous rod, broadening at its base and pointed 
at the apex, it measured about 4,5 mm in length. (Pl. VIIL, fie. 14.) 
PARMUNCULUS n. gen. 
oO 
In 1870 SEmreEr (3) described a small species of slug from Mindanao under the 
name of Tennentia philippinensis. From the few particulars given the main 
characters may be summarised as follows: the animal was vellowish- or reddish-gray, 
with a dark line on each side of the neck, running longitudinally on the mantle were 
two similar dark lines. The shell was rather flat and it showed a distinet apical whorl. 
Later writers have with few exceptions reearded this species as beloneine to the 
F te] } io oO 
genus Mariaella, but I think it will be evident to anyone acquainted with the anatomy 
