96 Psyche [March-June 
merous than in male (9 to 12 on each side) ; this preanal sclerite 
is flattened and completely bare on the ventral side, a striking 
peculiarity of the species. Apical portion of venter covered with 
very short setae arising from unusually large, sclerotized papulae. 
Otherwise as in male. 
Total length, from notch of fronto-clypeus to apex of ab- 
domen (alcoholic specimen): 8 mm.; length of wing: 7.8 mm.; 
width of wing: 2.7 mm. 
Specimens Examined. — Belgian Congo: Holotype, male, 
Mongende, off Cormorant, Halietor africanus (Gmelin) (H. 
Schouteden. — Congo Museum, Tervuren), — Kenya Col- 
ony: Allotype, female, Naivasha, off Phalacrocorax carbo lu- 
cidus (Lichtenstein) (A. Meinertzhagen. — Museum Comp. 
Zook, Cambridge). — Uganda: Male and female paratypes, 
Entebbe, off Halietor africanus and off Anhinga rufa rufa (Dau- 
din) (G. H. E. Hopkins. — Brit. Mus.). Female and male 
paratypes, Kampala, off Anhinga rufa rufa (G. H. E. Hopkins. 
— Mus. Comp. Zool.). Female and male paratypes, Bulen- 
gugwe, off Anhinga rufa rufa (W. G. Eggelius and G. H. E. 
Hopkins. — Brit. Mus.; Mus. Comp. Zook). Male and female 
paratypes, Katwe, Toro, off Anhinga rufa rufa and Phalacro- 
corax carbo lugubris Ruppell (G. H. E. Hopkins. — Mus. 
Comp. Zook). Male and female paratypes, Kome Island, Lake 
Victoria (G. D. H. Carpenter. — Brit. Mus.). — Ethiopia: 
Female paratype, Dambi Ford, in tent, probably off a Cormo- 
rant (Major Cheesman. — Brit. Mus.). Several specimens are 
infested with myialgid mites, the infestation being particularly 
heavy on one of the flies from Katwe, off Anhinga rufa. 
A study of a cotype of Olfersia palustris Ad. Lutz, Neiva and 
da Costa Lima (1915, Mem. Inst. Osw. Cruz, VII, p. 183, PI. 
XXVIII, fig. 4), from the State of Piauhy, Brazil, shows that I 
was mistaken in referring to that species the African parasite of 
Cormorants. The true O. palustris is one of the small species of 
Lynchia , the wing being about 5 mm. long. It is very closely 
related to, or possibly even identical with, Lynchia albipennis 
(Say). 1 
1 1 am indebted to the late Dr. Ad. Lutz for a cotype of Olfersia palustris , now 
deposited at the Museum of Comparative Zoology. I surmise that the length of 
the wing as given originally (7 mm.) was either an oversight or meant to cover 
the distance from the clypeus to the tips of the folded wings. It should be noted 
that the total length of the body as given (S mm.) is too small for any of the 
large species of Lynchia . 
