258 



Mr. B. F. Cummlnojs 07i the 



literature of this group *. Tliis sclerite (sometimes called 

 "lyriform organ " and homologized with tlie hypopharynx) 

 and glands (better known as basal pieces), almost unique in 



Fig. 1. 



Infra-buccal plate of Polyplax braehyrhynchus (Anoplura). The whole 

 of the top of the head has beeu dissected away, so that the plate is 

 seen from above. The bundle of elongated needle-like trophi, which 

 are sketched in only diagranimatically, have beeu drawn on one side 

 to leave the plate clear. 



MO = Mouth-opening ; D = Rostral denticles ; S = Infra-buccal plate 

 (or sclerite) ; C = Chitinous chords ; G= ? " Gland " (this was only 

 visible on one side). Greatest length of the plate = *013 of a milli- 

 metre ; greatest width = -016. 



the comparative anatomy of the insect-mouth, occur in their 

 typical form in tlie suborder Ischnocera of tiie Mallophaga 



* Vide V. L. Kellogg, Proc. Calif. Acad. Sci. vol. vi. 189G. "R. Snod- 

 grass, Trans. Am. Ent. Soc. xxxi. Nr. 4, 1905, pp. 297-307 ; P. Z. S. 1913, 

 p. 128. Armenaute, Boll, della Soc. di Naturalisti in Napoli, xxiv. 

 (ser. 2, vol. iv.) 1910, p. 76. 



