. Monographs of the Diptera of North America [microform]. Diptera; Insects; Diptères; Insectes. ORTALlDiEâSYSTEMATIC DISTUIUUTION. 45 the only diiTereuce sliowii by the hitter spfeies is a somewhnt smaller length of the third autennal joint. Next to these are some South African liioellise, for inslanec, Itiwllia utra L\v., which have the third antennal joint a little shorter still; ail these species, however, cannot be separated from Jtivcllin, as the dimi- nution of the third antennal joint is a very gradual one, not affording any distinct limit for a sei)aration, Macijuart's VAnuKHMA fascip
. Monographs of the Diptera of North America [microform]. Diptera; Insects; Diptères; Insectes. ORTALlDiEâSYSTEMATIC DISTUIUUTION. 45 the only diiTereuce sliowii by the hitter spfeies is a somewhnt smaller length of the third autennal joint. Next to these are some South African liioellise, for inslanec, Itiwllia utra L\v., which have the third antennal joint a little shorter still; ail these species, however, cannot be separated from Jtivcllin, as the dimi- nution of the third antennal joint is a very gradual one, not affording any distinct limit for a sei)aration, Macijuart's VAnuKHMA fascipennis, from the Cape, is likewise but very little dill'orent Irom the typical ItivcUise. The occiput is somewhat more convex ; the third antennal joint has a some- what sharper anterior angle, the thorax is comparatively a little smaller, and the first section of the fourth longitudinal vein shows but very little of the sinuosity, so characteristic of the true Rivcllise, and which renders the anterior part of the discal cell more narrow; at the end of the convex scutellum there are two strong bristles: whether the second pair of bristles, which exists in the other liivellifr, is wanting here, or whether they were accidentally broken off in the specimen I had before me, I am unable to decide; I rather incline to favor the former suppo- sition. If I am right, Epnlesma would deserve to be retained as a separate genus; in the opposite case, it would be better to place Epidcs^na fascipcnnia in the genus liivellia, l)eeause then the whole difference between them would merely consist in com- parative characters. Among the species from the sontheart of Asia, there are several which are closely allied to lUvellia, but differ from tlio typical species in the greater length and lesser breadth of the marginal cell, a more straight third longitudinal vein, and a hardly perceptible sinuosity of the first section of the fourth vein ; moreover, the thorax is less strongly developed, so that
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