46
THE ESSEX FIELD CLUB.
Mr. Crouch called attention to the specimen of the Bittern, recently
found in the Zoological Gardens, at Regent's Park.
Mr. Cole observed that the Bittern still occasionally occurred in Essex.
It was formerly found in the valley of the Roding.
The Secretary exhibited on behalf of Mr. Whitehead, the Assistant in the
Museum, a specimen of Lathyrus macrorrhizus var. tenuifolius, from Epping
Forest, near Goldings Hill. There was some doubt as to the specific distinct-
ness of the form, and it was not at present known whether it was common in
Essex or not.
Mr. F. W. Elliott exhibited bones found in the Forest at Monks Wood,
which had been gnawed by some rodent—he suggested by rabbits.
Mr. Cole mentioned the curious fact that although there were so many
deer in the forest, antlers were but seldom found. Foresters affirmed that
they were eaten by some animals.
An address was then delivered by Prof G. B. Howes, LL.D., F.R.S.,
Professor of Zoology at the Royal College of Science, illustrated by slides
shown by the electric lantern. The following is an abstract of the address :—
RECENT WORK ON MOLLUSCAN MORPHOLOGY.
By PROF. G. B. HOWES, LLD., F.R.S.
(Abstract).
Prof. Howes introduced his subject by briefly recapitulating the distinc-
tive characters of the Acephala, with especial reference to the fact that under
the burrowing habit and loss of the head respiratory organs had become the
accessories to alimentation. He then called attention to the recent work of
Drew, of Baltimore, U.S.A., on Yoldia limatula, particularly as concerning the
labial palps, siphonal filaments, and piston-like action of the branchiae, which
together with the formation of the anchor-like foot, were shown to collectively
furnish the acme of the physiological requirements of the acephalous
molluscan type.
He then passed on to the consideration of the Trochosphere and Veliger
larvae ; the former as exemplified by that of a marine worm; the latter by
that of the oyster with special reference to the absence of the "head" ; and
by the late larva of Vermetus, as bearing upon the origin of the cephalic eyes.
Attention was then turned to the recent discovery, by Pelseneer, of eyes
in the adult Mytilidae, those of Mytilus being shown to be structurally of the
Patella type, but post-oral, and, though innervated by the cerebral ganglia,
distinct from the cephalic eyes of other molluscs. They were shown to agree
in position with the post-velar eyes of the Chiton larva, and thereby to suggest
a close connection between the Lamellibranchiata and Polyplacophora
(Chitons). The limits of modification and salient features in the anatomy of
the Chiton group were next indicated, leading up to the aplacophorous genus
Myzomenia (Dondersia) and special emphasis was laid upon Pruvot's recent
discovery that M. banyulensis during development is the bearer of the
eight shelly plates of the true Chitons, and that the development itself
is passed through within a cellular "test,'' from which the young mollusc
escapes by a process of rupture. Referring to this "test" and its