108 REPORT—1857. 
as a species of antelope with one horn placed unsymmetrically on his head. When my 
brother Hermann was in Nepaul, he procured specimens of horns of a wild sheep 
(not of an antelope) of very curious appearance. At first sight it seemed to be but 
one horn placed on the centre of the head; but on closer examination, and after 
having made a horizontal section of the horn, it was found to consist of two distinct 
parts, which were included in a horny envelope, not unlike to two fingers put in one 
finger of a glove. The animal when young has two separate horns, which are how- 
ever placed so close to each other, that the interior borders begin very soon to touch 
each other ; later, by a slight consequent irritation, the horny matter forms one un- 
interrupted mass, and the two horns are surrounded by this horny substance, so that 
they appear at first sight to be but one. 
In conclusion, allow me to say a few words about migratory birds. There are no 
migratory birds in the Himalayas ; we nowhere and at no season found flocks cross- 
ing the Himalayas, as many birds of Europe cross the Alps, between Italy and Ger- 
many. The Himalayan birds do not change their abodes on a large scale; the 
different various heights themselves afford them the opportunity to select the climate 
they require in different seasons. In the plains of India, however, chiefly in Bengal, 
a large number of birds disappear during the breeding time ; they do not, however, 
leave India altogether, but select their abodes in the lower, impenetrable jungles of 
the delta of the Ganges and Brahmapootra, called the Sunderbunds, where they were 
found by my brother Hermann in large quantities, whilst at the same time they had 
entirely disappeared in Bengal Proper. 
On the Reproductive Zooids of Comatula rosacea. 
By Professor WyviLLe THOMPSON. 
On Dredging in Weymouth Bay. By W. Tompson. 
The results of a day’s dredging in Weymouth Bay, by Mr. Thompson, were read, 
by which it appeared that he had obtained thirteen species of Conchiferous Mollusks ; 
two of fish; eight of Crustacea; two Nudibranchiate Mollusks ; four Tunicated 
Mollusks; four Actiniade; one Cirrhipede ; one Medusa (floating); three Sponges; 
three Radiata; and nine Annelides. 
Mr. Thompson also drew attention to the gregarious habit of Doris bilamellata 
in early spring, when they approach the shore for the purpose of depositing their 
coils of ova. 
He also drew attention to the constancy with which certain parasites in the dif- 
ferent families of nature are always found in the same species, and he instanced 
Adamsia palliatia as always found on Pagurus Prideauwit; Sagartia parasitica on 
Pagurus Bernhardus ; Halichondria suberea on Pagurus Forbesii, and very seldom on 
Pagurus levis; Hydractinia echinata on Pagurus Bernhardus. Pecten opercularis, 
when young, is always attached by a byssus, and Pecten varius is attached through- 
out its existence. : 
The dredging ground was on a rough shingle and coralline bottom in 10 fathoms 
water, in Weymouth Bay, about four miles from the shore. 
Notes of a Visit to Mitchelstown Caves. 
By Dr. E. Perctvat Wricut, Director of the Dublin University Museum. 
The author stated, that in company with Mr. Halliday, he, in the early part of 
August 1857, explored the extensive limestone caverns situated in the valley of 
Mitchelstown, between the Galtee and the Knockmildown ranges of mountains; the 
object of the visit being to examine whether any of the curious blind animals, so well 
known as inhabiting the Carniola and other caves, could be found in Ireland. 
He gave a brief sketch of the geology of the district, of the various blind insects 
found on the continent and described by Schiodte, and of the Mitchelstown Cave, of 
which a ground-plan was exhibited ; and then stated that in the interior of the cave, 
and near some small pools of water formed by the dropping from the roof, specimens 
of a small white Lipura were discovered. This insect comes very near to the species 
figured by Schiodte, found in Adellesburg Cave; but on a very careful examination 
