166 Mr. R. M‘Lachlan’s Monograph of the 
to separate them, at the time when his Collection was sent to the 
Colony of Victoria. The character given in the description of 
T. pullata, ‘superior wings with a few obscure whitish spots,” is 
imaginary; perhaps these wings were marked by the fingers in the 
capture of the insect. Of the species of Rhyacophila described by 
Pictet, R. penicillus, melas, barbata, nigrocincta and articularis, pro- 
bably all belong to Berea ; the few types existing are females and 
indeterminable. Of the species described by Stephens, the types of 
B, albipes are absent from his Collection, and those of the other 
two species are unfortunately females. Kolenati admits three 
species, but appears to have been personally acquainted with one 
only ; this I cannot identify with any of ours. We probably pos- 
sess more species than are here given; I am acquainted with at 
least one other Continental species.* 
I am doubtful as to the propriety of superseding Curtis’ generic 
name Thya, which has the right of priority. That name was cer- 
tainly employed previously by Dr. Leach to designate a genus of 
Crustacea, but the two genera are never likely to be confounded. 
The strict application of the rule that forbids the identity of 
generic names in the Animal Kingdom (and some writers would 
even apply this to the whole range of natural productions), is 
productive of great inconvenience, and is driving modern authors 
to the creation of names, purely imaginary, and which admit of 
no explanation. 
1. Berea pullata, Curtis. 
(Pl. VII. fig. 9, neuration; Pl. XIV. figs. 16, 17, app.) 
Lhya pullata, Curt. Phil. Mag. p. 215, 7 (1834) ?; Berea 
albipes, Steph. Ill. p. 158, 1 (1836) ?; 5B. Marshamella, Steph. 
lll. p. 158, 3 (1836) ?. 
Antenne, head, palpi, thorax, wings and abdomen black. 
* Mr. Eaton has taken, at Cambridge, in 1865, a minute black insect with 
the facies of Berea, which appears to be identical with Silo minutus, Kol. (Gen. 
et Spec. Trichop. pt. 1, p. 101, 1), and probably with Phryganea minuta, 
Linn. (Faun. Suec. n. 1501). Dr. Hagen has compared Mr. Eaton’s insect 
with types of §. minutus sent to him by Kolenati, and also with specimens sent 
by him to Kolenati, and named by the latter. But it is to be remarked that, 
according to the generic description, Kolenati’s Silo should have 2-4-4 spurs, 
whereas our insect has only 2-2-4, and the figure of the neuration does not 
agree ; however, in the face of this double determination, there can be no 
doubt that this generic description is erroneous. The insect is probably allied 
to Berea, but differs considerably in the neuration. I have not sufficient 
materials in hand for a description. As before mentioned (p. 82), Kolenati 
misapplied Curtis’ generic term Silo; and a new name willhave to be adopted 
for this species. 
