482 .  Loological Society:— 
head 31 inches, its depth about 1} inch. The stretch of wings 
is 28 inches across. 
The most remarkable features in this animal are its large hammer- 
shaped head, and the great external development of its lips. Its 
whole structure is essentially that of a Pteropine Bat, with some 
modifications showing a tendency towards the Rhinolophi. No 
species having any of the nasal appendages peculiar to that section 
of the Bats has yet been found among the Pteropine Bats. They are 
strictly frugivorous, and have the nose like that of a fox or dog. 
The present species, although it has not any nasal appendages, has 
labral expansions which may possibly be analogous to them, and the 
animal may possibly have peculiar habits to which the structure of 
these organs is especially adapted. 
Unfortunately, in the only specimen yet received, the stomach and 
intestines were wholly empty; so that we cannot speak of its food 
with positive certainty. The teeth are Pteropine in character, but not 
so absolutely so as to preclude the possibility of this creature being 
at least partially insectivorous, the molars showing a tendency to 
mammuillation on the external side of the longitudinal ridges into which 
they are separated. The large folds in the interior of the stomach 
seem to point to a vegetable diet. 
The sublingual fringed membrane is also an interesting peculiarity, 
not only on account of its rarity, but because one of the few 
other instances where it has been noticed is in an animal having no 
one thing in common with the present, except that of living in the 
same country. We sometimes see this happen; an abnormal struc- 
ture or peculiarity occurring in an animal restricted to one country 
will be found repeated in some other animal of that country no way 
connected with or allied to it. 
This Bat was sent to me by my excellent friend, the Rev. Wm. C. 
Thomson, one of the missionaries of the United Presbyterian Church 
of Scotland, stationed at Old Calabar—a true Christian, an excellent 
naturalist, and one whose devotion to the cause he has undertaken, 
viz. the amelioration of the African negro, has been proved by the 
greatest sacrifices from his youth upwards. 
Prof. Owen communicated the first part of his paper on the Aye- 
aye (Chiromys madagascariensis, Cuv.), including an introductory 
historical sketch of its discovery and the various opinions respecting 
its nature and affinities set forth by naturalists from Buffon to the 
present time. After commenting on the chief of these, the author 
proceeded to narrate the circumstances under which the subject of 
his descriptions, a nearly full-grown male, had been obtained from 
Madagascar, and prepared for dissection, by the Hon. H. Sandwith, 
M.D., C.B., whilst Colonial Secretary at the Mauritius. The habits 
of the Aye-aye during the period in which it lived a captive at the 
Mauritius with Dr. Sandwith, and also the habits of other individuals 
that for a time were kept alive in the island of Réunion, by MM. 
Liénard and Vinsor, in 1855, were next noticed. The specimen sub- 
mitted to Prof. Owen, having been transmitted well preserved in 
