ur 
et 
had sent to me for identification a specimen of a slug from Mindoro which I was about 
to desceribe as the type of a new genus when the genus Philippinella was established. 
My best thanks are due to Mr. Surtu for placing the same in my hands. 
The main objeet of the present communication is to a) give a fuller and more 
detailed description of the external characters and anatomy of the genus, so far as the 
present material will admit, b) to enumerate the species belongine to the genus which 
are at present known, c) to trace, so far as our present knowledge will permit the affi- 
nities of the genus, and d) to show that Semrer’s Tennentia philippinensis does 
not belone to this genus, being more closely allied t Parmarion. 
I venture to appeal to zooloeists travelling in the Philippine Islands for more 
material in order that a fuller and more detailed account of tie anatomy may be given. 
en Genus PHILIPPINELLA, Mrrorr. 
The external features somewhat resemble those characteristic of Mariaella, Gray: 
the visceral mass is larger than in that genus, extending more posteriorly. The mantle 
is smooth and completely covers the shell, there being no pin-hole pore; there is a well- 
defined keel which may either lateral or dorsal, and is divided into richt and left halves, 
the latter being the larger. The shell is a thin, flat, calcareous plate covered by a dark 
amber or horn coloured periostracum, which overlaps the edees of the plate; there is 
no trace of an apical whorl. 
The dart-sac is considerably larger than either the penis or receptaculum seminis, 
and is folded upon itself, there is a small caleareous dart situated at the commencement 
of the dart-sac; the vas deferens terminates by an enlargement near the proximal end 
of the short penis, there is no flagellum. 
It will be convenient to group the known species of this genus under two divisions 
viz. those in which the keel is laterally produced and those in which it is dorsal. In 
the former group it seems very probable that the lateral wing-like overlappings of the 
mantle represent the dorsal keel of P. möllendorffi. 
Division a) Keel produced into lateral wing-like expansions of the mantle. Exs. 
P. quadrası, MLLDFF. and P. carinata, MLLDFF. 
Division b) Keel dorsal, well developed. Exs. P. möllendorfti. 
P. QUADRASI, Mrivvrr. 
Tennentia quadrasi, MLLDFr., 1894, Nachr. d. Deutsch. Malak. Gesell., p. 85. 
Aminal brownish yellow, darker on the smootlı dorsal portion of the mantle. 
Mantle convex, completely covering the shell; anteriorly finely granulose, posteriorly quite 
