Frederick Knab.
A Review of our Species of Trigonometopus (Diptera; Lauxaniidae).
Psyche 21(4):123-126, 1914.

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19141 Knab-Review of our Species of Trigonornetopus 123 THE DISCOVERY OF ECLIMUS HARRIS1 IN THE WHITE MOUNTAINS, N. H.
BY CHARLES W. JOHNSON,
Boston Society of Natural History.
This interesting species has long been known only by the type, a male, in the Harris collection, in the Boston Society of Natural History. It bears the label, "H. Gray," without date or locality. It was described by Osten Sacken as Epibates harrisi in his Western Diptera (Bull. U. S. Geol. Survey, Vol. 3, p. 273, 1877). In the note following the description he says: "It is probably from the Northern United States as are nearly all the specimens in the collection." On page 271 ~JI the table of species it is referred doubtfully to the "Atlantic States (?)," but in the table of con- tents where all the species are arranged systematically with local- ities, "Massachusetts" is given without a question. I am unable to find any authority for this and doubt if Osten Sacken made the table of contents.
During the meeting of the New England Federation of Natural History Societies at the Glen House the first week in July, frequent collecting trips were made to various parts of the mountains. On July 8, I captured a male of Eclimus harrisi on the flowers of the blackberry on the Mount Washington Road near the Raymond trail, just below the two-mile post, at an elevation of about 2,600 feet. This resembles the type in every respect except that its length is 12 mm. while the type measures 14 mm. A female of this species was taken by Mr. C. A. Frost, July 6, along the railway, above Base Station.
A REVIEW OF OUR SPECIES OF TRIGONOMETOPUS (DIPTERA; LAUXANIIDB) .
BY FREDERICK KNAB,
Bureau of Entomology, Washington, D. C.
The Lauxaniid genus Trigonornetopus is easily recognizable by the peculiar shape of the elongate head, triangular in profile, with the frons horizontal and the face strongly receding, the antennae nserted at the apex of the triangle. Four species have been



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124 Psyche [August
described from America, three of which are represented in the national collection by single specimens. Four other specimens in the collection belong to two species hitherto undescribed and are now characterized. The European species, Trigonometopus frontalis Meigen, frequently has the last section of the fourth vein appendiculate; none of the specimens before me show this peculiar- ity. The American species may be separated as follows: 1. Wings subhyaline, two round dots on outer section of third vein punctipennis Coq.
Wings not so marked. ............................................... .2 2. Wing pale along the costa, a dark streak medially ....................... .3 Wings not so marked. ............................................... .5 3. Abdomen mostly pale. ..................................... wittatus Loew Abdomen dorsally black, marked medially with yellow ................ .4 4. Wings with a dark spot on the anterior cross-vein, median stripe of abdomen to tip. ............................................. albzfrons sp. nov. Wings without spot on anterior cross-vein, median stripe of abdomen abbre- viated ......................................... angustipennis sp. nov. 5. Wings whitish hyaline, reticulated with fine bars of black between the veins reticulaius Johns.
Wings not reticulate, a dark shade along costa involving second vein rolundicornis Will.
Trigonometopus angustipennis sp. nov.
Male: Frons pale brownish, moderately broad, narrowing very slightly ante- riorly, the part in front of the eyes not broadened; a dark patch clothed with dense black hairs laterally from eyes to antennae; occiput dark brown along posterior margins of eyes, a black streak from eyes along lower margin of cheek. Antennae ferruginous, the third joint compressed, in lateral view broad and rounded; arista long, pale at base, black beyond. Mesonotum and scutellum black, with three narrow, well-defined, longitudinal yellowish stripes, confluent on anterior margin, posteriorly continued over the scutellum. Pleurae ocher yellow. Abdomen dorsally black, a median yellowish stripe extending to the apex of the fourth seg- ment; sides and venter yellowish. Legs yellowish, the tarsi slightly infuscated, Wings rather narrow, the costal region to the middle of the submarginal cell pale yellowish, subhyaline, the involved veins pale; the rest of the wing smoky, a dis- tinctly darker median streak involving the third and fourth veins and near the tip of the wing extending forward to the costa and involving the tip of marginal cell; all the veins within the smoky zone black, a dark shade along the fifth vein and posterior cross-vein. Length: Body about 4.5 mm., wing 4 mm. Guadeloupe, West Indies, 3000 feet altitude, 30 July, 1905, one specimen (Aug. Busck) .
Type: Cat. No. 18482, U. S. Nat. Mus.




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10141 ~nabÌÔlUvi of WIT Species of Trigoim&ps 195 In this species the ocular margins converge slightly anteriorly while in the two species which follow they are distinctly divergent; beyond the bulging eyes the from is not markedly broadened, aa is the case in the other species. The head is also slightly shorter in the portion beyond the eyes. In the single specimen the head is somewhat distorted, nevertheless the differences from T. aibi- fions, the species it most resembles, are obvious and abundant. Male andfewwie: Fiona creamy white, very broad, widening anteriorly, a large dark brown spot densely clothed with black hairs laterally before eyes, scattered black hairs anteriorly diminishing to behind the middle; occiput dark brown along pasteriot margins of eyes to the cheeks, a dark streak from the eye along the lower margin of the cheek, face white, nearly flat. Anteme' whitish, the third joint tinged with ferruginous, compressed beyond its base, in profile broad and rounded; arista very long, pale near base, black beyond. Thorax narrow; mesonoturn broadly blackish brown at the sides, a median yellowish acne occupying nearly half ita width and divided by two ill-defined dark stripes into three pale longitudinal stripes. Sciitellum blackish brown, with a narrow median and less distinct lateral yellowish stripes. PIeuirte pale yellowish, infuscated on the mesostemurn. Abdomen dor- sally black, with pale lateral incisions and a median yellowish stripe extending its entire length; venter pale. Legs pale yellowish, the bristles black; tarsi veiy slightly infuscated, Wings lather broad, the costal region to the middle of the su bniftrginal cell pale yellow, semi-opaque and with the veins pale; posterior portion of wing tinged with grey and with all the veins behind the second black, a darker shade about the cross-veins and broadly dong the third vein, particiilarly distally where it 13 abruptly produced to the anterior margin at the tip of the second vein. Hftlteres pale, with infuscated knobs. Length: Body about 4.2 mm., wing 8.5 mm.
Sun Murcos, Nicaragua, 9 specimens (C. I?. Baker) ; Cacao, Trece Aguas, Alta Vera Paz, Guatemala, 30 March, 1906, one specimen (Schwarz and Barber).
Type: Cat. No 18481, U. S. Nat. Mus.
The specimen from Guatemala differs in some respects. On the wings the anterior expansion of the dark shade reaches the costa before the end of the second vein, thus involving the tip of the marginal cell; the portion of the second vein within the dark shade is black. I attribute no significance to this difference, aa the two specimens from Nicaragua, which are surely conspecific, show variation in this respect. In one the dark shade reaches the costa at the tip of the second vein, in the other the pale costal zone extends a short distance beyond the end of the second vein.



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