156 INSECUTOR INSCITlyt MENSTRUUS 



Simulium bipunctalum Malloch, Proc. U. S. Nat. Mus., xliii. p. 650 (Dec. 31, 

 1913). 



The types of Simulium bipunctalum in the U. S. National Museum 

 agree very closely with Miss Joan's very detailed description and figures. 

 The only discrepancy is in the size and this can not be given much 

 weight, particularly as Miss Jocin seems to have erred in her measure- 

 ments. She states that her specimens measured from 2.5 to 3 mm. in 

 body length and that the wings do not exceed 2.5 mm. Her figure, 

 however, shows that, as in other species of Simulium, the wings are con- 

 siderably longer than the body. Assuming that the error is in the body 

 measurement, there is still a discrepancy in the length of wings, those of 

 S. bipunctalum measuring about 2 mm. ; but it is clear that the species 

 can not be kept separate on this difference alone. As to the distribu- 

 tional data, Miss Joan's specimens are from Alpachiri, in the province of 

 Tucuman (Argentine), and the others are from the Rio Charape in east- 

 ern Peru. Both localities are on the eastern slopes of the Andes and 

 not too remote from each other. 



In closing a word should be said concerning what Miss Joan calls 

 " autohemorrhea " in Simulium dinellii. Mr. Dinelli, who observed the 

 insect in nature, communicated to her the following observation : " I have 

 seen that as soon as they begin to swallow blood they expel a clear 

 liquid, which, at intervals, they project backwards, forming a globule 

 which gradually evaporates ; it appeared to me that the discharged liquid 

 was an overlarge quantity and that it could not have been contained in 

 the very flaccid abdomen ; I suppose that during sucking the separation 

 of the serum from the red corpuscles takes place and that the former is 

 immediately expelled." ^ Miss Joan expresses the belief that the liquid 

 discharged by the Simulium is its own blood and that the phenomenon 

 is comparable to the " bleeding " such as occurs in certain Coleoptera at 

 the femoro-tibial articulation. There can be little doubt, however, that 

 the liquid discharged was contained in the digestive tract and was not 

 from the body cavity. A similar phenomenon has been observed in 

 certeiin mosquitoes, and here the liquid is ejected to maike room for the 

 newly imbibed blood. 



' Joan, 1. c. p. 383. 



Date of publication, December 3 1 , 1913. 



