46 PROCEEDINGS OF THE NATIONAL MUSEUM vol. los 



In the collection are five slides labeled ^'Phthirus gorillaeJ' Three 

 of the slides contain only eggs, and since Ewing described just the 

 first stage nymph the eggs need not be considered in type selection. 

 Of the two nymphs, one bears the following data: Left; "Type No. 

 40161 U. S. N. M., Phthirus gorillae n. sp., 1st nymph"; Right: 

 "Belgian Congo, 1923, by Benj. Burbridge, from young gorilla, 

 U. S. N. M. 239884." The other slide has, on the left, "Phthu-us 

 gorillae Ewing, 1st nym.," and, on the right, "Belgian Congo, Rec'd 

 Jan., 1924, Benj. Bm-bridge, from skin of young cf gorilla (U. S. N. M. 

 239884)." Although this second specimen is not marked as a type, 

 Ewing mentions "nymphs" in his description, making the selection of 

 a lectotype necessary. The nymph with the type label USNM 40161 

 is selected as lectotype. 



Pkesent status: The taxonomy of the genus Phthirus is in a 

 chaotic state. Ferris (1951, Mem. Pacific Coast Ent. Soc, vol. 1, p. 

 281) has pointed out that the description of this species merely 

 demonstrates the occurrence of a species of Phthirus on the gorilla. 



Genus Polyplax Enderlein 



Polyplax alaskensis Ewing, Proc. Ent. Soc. Washington, vol. 29, No. 5, p. 118, 

 1927. 



Type data: USNM 40159. Holotype male from Microtus sp. from 

 Alaska. 



Present status: As originally described. Figures of the holotype 

 of P. alaskensis have been published elsewhere (Scanlon and Johnson, 

 Proc. Ent. Soc. Washington, vol. 59, p. 282, fig. 3, 1957). 



Polyplax dentaticornis Ewing, Proc. Biol. Soc. Washington, vol. 48, p. 207, fig- 

 c, 1935. 



Type data: USNM 44905. Holotype male and a last nymph from 

 the skin of Cricetulus andersoni [Cricetulus longicaudatus andersoni] 

 (USNM 172610), Shansi, China. 



The holotype male and last stage nymph are on separate slides and 

 both bear the above data. 



Present status: Until more specimens from the type host are 

 examined, the status of this species must remain in doubt. In the 

 holotype, most of the para tergal plate setae are missing, and the 

 third pair of legs is missing. The shape of the thoracic sternal plate 

 and the fact that one seta on paratergal plate four is longer than the 

 plate suggest that P. dentaticornis is closely related to P. serrata 

 (Burmeister) and might be an aberrant specimen of this species. It 

 should be noted that Ewing's figure of the third antennal segment of 

 the holotype (loc. cit., p. 203, fig. c) pictures the apical spine as a 

 lobe rather than a spine. This mistake was probably due to the fact 

 that the entire head is flattened, changing normal relationships of the 

 various parts. 



