26 HENRY F. CARTER. 



the outer side at the apex, and with three of the bristles of the posterior transverse 

 distal row (situated on the inner aspect) replaced by similar but smaller spines ; 

 metatarsi, particularly those of the hind legs, short, fore and hind metatarsi incrassate ; 

 fore and hind tarsi with stout, blunt black spines arranged as shown in fig. 10, 

 middle tarsi with six or seven pairs of similar spines on the first segment and the 

 apical bristles of the second and third segments differentiated — spine-like. Claws 

 (fig. 10, e) equal, the basal tooth stout. Abdomen translucent creamy white, but 

 appearing in engorged or partly fed specimens dark brown or cream-coloured, with 

 dark central bands on the proximal segments ; clothed with pale hairs. Lamellae 

 creamy white, clothed with pale hairs. Spermathecae two in number, heavily 

 chitinised, oval {53/iix37/n) ; the commencement of the duct chitinised for a 

 relatively long distance (IS^w). 



Habitat. Zanzibar {Dr. W. M. Aders), seven females (including three cotypes). 

 The labels attached to the specimens bear the following data : on buffalo ; Pigaduri^ 

 Za,nzibar, 13.iv.l9. In the collection of the Imperial Bureau of Entomology. 



Acanthoconops albiventris, de Meijere. 



Leptoconops albiventris, de Meijere, Tijds. voor Ent. Iviii, p. 98 (1915). 



Leptoconops spinosipes, Kieff., Ann. Mus. Nat. Hung, xv, p. 190 (1917). 



?• — Length of body (two specimens), 1-8 mm.; length of wing, 1-0 mm.; 

 length of antenna, 0-3 mm. ; width of head, 0-32 mm. 



Through the courtesy of Professor de Meijere, I have been able to examine females 

 of this species, which was described by him from specimens collected in New Guinea. 

 This author noticed and commented upon the unusual form of the lamellae, but 

 retained the species in Leptoconops, and apparently did not observe closely the 

 arrangement of the hairs on the head ; this he stated was " kaum behaart." 

 A. albiventris is closely allied to the preceding species, but is smaller, and possesses 

 somewhat less powerful, though similarly arranged, spines on the legs. Morpho- 

 logically, it may readily be separated from A. spinosifrons by (1) the frons bearing 

 numerous short hairs or bristles instead of spines ; (2) the terminal segment of the 

 antennae being relatively longer (equal in length to the preceding three and one- 

 third segments instead of the preceding two and one-half) ; (3) the bristles forming 

 the posterior transverse distal row on the hind tibiae all being normal, none replaced 

 by spines ; (4) the hind metatarsus being relatively longer (about one-half the length 

 of the tibiae, whereas in A . spinosifrons it is about one-third the length) ; and (5) the 

 tooth of the claws being distinctly smaller. 



The synonymy given above seems extremely probable from a comparison of the 

 descriptions, and in view of the fact that Kieffer's specimens also came from New 

 Guinea (Tamara, Berlinhafen). Discrepancies in the descriptions are slight, and 

 Kieffer's statement that the abdomen is red, sometimes white, with brownish 

 markings, is of little consequence, as it suggests that some (possibly most) of his 

 examples were wholly or partly engorged with blood. 



This species appears to be a vicious biter and, at times, a serious pest in parts of 

 New Guinea ; K. Gjellemp, the collector of de Meijere's material, attached the 

 following information to the specimens — " An der Mundung des Sermowai-Flusses 

 in sehr grosser Anzahl vorhanden und durch ihr Stechen eine grosse Plage bildend, 

 16 Mai 1911." 



The distinguishing characters of the known species (females) of Leptoconops {sens. 

 lat.) and Acanthoconops are summarised in the following table. 



(1) Lamellae elongate ; frons bare or with a single pair of hairs between the 



eyes {Leptoconops, sens, lat.) . . . . . . . . . . . . 2 



Lamellae very short ; frons with numerous spines or hairs {Acanthoconops) 17 



