Diptera 57 c 
penultimate ventral segment in the arctic species has more numerous anterior 
spines than has pratti, and there are several spines along the latero-ventral 
margin which I do not find in the latter. The apical spines are much more 
numerous in the arctic species than in pratti. 
TACHINID^. 
The larvae of nearly all of the species of this family are internal parasites 
in other insects, mostly in the larvae or pupae. 
There are only two species in the collection. 
Euphorocera gelida Coquillett. 
Euphorocera gelida Coquillett, Revision of the TachinidiB. Tech. Ser., No. 7, U. S. Dept. 
Agr., Bm-. Ent., p. 101, 1897. 
There are thirteen specimens of this species in the collection. 
Four of the specimens differ from the others, and from the original descrip- 
tion, in having only three pairs of postural dorso-centrals. In other respects 
the specimens of both lots agree perfectly. 
Pinned with several of the imagines is the empty puparium from which the 
insect emerged. A comparison of these puparia with those of Euphoi'ocera 
claripennis Macquart shows that the two species are not congeneric. The 
characters of the puparium of gelida are as follows: — 
Brownish red, subopaque; posterior spiracles black-margined, glossly. 
Surface microscopically, transversely striated; incisions between segments 
defined by a single series of short stitch-like impressions; each abdominal 
segment with three small depressed areas on centre of side, in each of which 
there is an irregular line of minute elevations visible only under a high-power 
lens; no respiratory elevations at base of abdomen; anal opening minute, consider- 
ably proximad of apex of abdomen, surrounded by a poorly defined granulose 
area; spiracles large, slightly elevated, especiallv above, general appearance and 
slits as in PL VIII. fig. 15. 
Length, 8-9-5 mm.; width, 3-3-75 mm. 
The puparium of claripennis differs in having the posterior spiracles with 
openings very pronouncedly sinuous, almost W-shaped as in Muscidse, the 
segments with distinct though miscroscopic locomotor spinules, and the respira- 
tory organs at base of abdomen in the form of stalks. 
Locality: The specimens of gelida are from Camden bay, and Demarcation 
point, Alaska, June and July, 1914 (F. Johansen). 
The puparia were from inside of the cocoons of a lepidopteron, Dasychirus 
sp. (?), sometimes as many as six in one cocoon. The records show that the larvae 
of the host do not succeed in pupating. (Rearing 10). 
Peleteria Robineau-Desvoidy. 
This genus is represented in the collection by a single female. 
Peleteria arctica, n. sp. 
Female. — Black, shining. Head black, cheeks except near posterior margin, 
face and its sides reddish yellow, densely white pruinose; interfrontalia reddish; 
orbits black, shining, but obscured by grey pruinescence; antennae and arista 
bl^ick; proboscis black, palpi ferruginous. 
Thorax slightly grey pruinose, not distinctly vittate; scutellum reddish 
yellow. Abdomen black, slightly grey pru,inesce,nt on bases of segments; sides of 
second and third segments broadly reddish. Legs black, hind tibiae reddish. 
Wings slightly greyish. Calyptrae white. Halteres dark brown. 
