8030 THE ZooLoGist—APRIL, 1872. 
Exhibitions, éc. 
Mr. M‘Lachlan brought before the notice of the meeting an illustration 
of the manner in which the ravages of Aphides are checked by parasitic 
Hymenoptera. He exhibited a portion of poplar-twig from Dr. Knaggs’s 
garden at Kentish Town, which had been occupied by a large family of dark- 
coloured Aphides; of these nothing now remained but their empty inflated 
skins, each of which preseuted a circular opening, whence the parasite 
(probably an Aphidius) had emerged, the whole bearing much resemblance 
to a collection of empty egg-shells of some large Lepidopterous insect. The 
portion of poplar-twig was less than an inch in length, and on it were nearly 
one hundred of these empty skins. 
Mr. Herbert Druce exhibited a large selection of Rhopalocera from Costa 
Rica, being part of a collection formed in that country by Dr. Van Patten. 
In all there were probably nearly fifty new species in the collection, 
including four of Papilio, three of Morpho, three or four of Leptalis, a new 
genus of Satyride allied to Pronophila, &c., &c. These are in course of 
description by Mr. Butler, in ‘ Cistula Entomologica.’ 
Prof. Westwood exhibited specimens and drawings of various species of 
Acaride and other aberrant Arachnida, either entirely new to Science or 
not previously observed in this country, as follows :— 
1. Fam. Trogulide. A small species of the genus Trogulus, differing 
from any of those figured by Koch, captured by the Rey. O. P. Cambridge 
in moss at Bloxworth, Dorsetshire; described by Prof. Westwood as 
T. rufitarsis. 
2. Genus Stylocellus, Westwood. A new genus pertaining to the recently 
instituted family Cyphophthalmidew (Joseph, in Berl. Ent. Zeit., vol. xiii.), 
founded upon a species (S. sumatranus, Westw.) from Sumatra, forwarded 
by M. Snellen van Vollenhoven as a new species of Trogulus. Differing from 
Cyrphophthalmus (the type of which is a minute species from the caves of 
Carniola) in having the chelicere shorter than the palpi, and with the terminal 
dactyls of the former simple and very acute, and the cephalothorax without a 
deeply incised emarginate mark, each side being produced into a short obtuse 
horn. Long. 7} mm. A second species (S. javanus, Westw.) is in the 
Collection of the British Museum. 
3. Argas reflexus, Latreille. Type of a family and genus not hitherto 
recorded as British. A colony of this species had been found by Mr. Gulliver 
under a stone in the crypt of Canterbury Cathedral. It ordinarily infests 
pigeons on the Continent, and the colony had probably originated from 
individuals that had fallen from the flocks of those birds frequenting the 
Cathedral. (Mr. F. Smith added that specimens of the dog-tick had been 
forwarded to him that had been found in the same Cathedral, and he has 
since furnished information to the effect that the British Museum possesses 
an example of the Argas from the same building.) 
