136 



MR. B. F. CUMMINGS ON THE 



Amblycerau genera Trinoton, Ancistrona, etc. The glands are 

 almost completely transformed into lateral pieces (text-fig. 27, D), 

 but may still be represented by an indistinct circular impression 

 on each lateral piece in front where it is joined by the delicate 

 ducts which are supported by a forked piece of chitin, homologous 

 probably with the forked piece in Trinoton and others. The 

 oesophageal sclerite is of a peculiar form, quite different from 

 that of other Dochophori and Ischnocera. It is not visible 

 without dissection. 



Tetrophtalmus titan Piag. (formerly M. titan) [from the 

 Pelican]. — The rami of the broad " duct " bifurcate far forward 

 at the front margin of the labium. No traces of the " glands " 

 (text-fig. 28, p. 135). In Pseudomenopon tridens (formerly 

 M. tridens), the hypopharynx is very similar, but the lateral pieces 

 are narrow in front where they run into the rami. 



Text-tig. 29. 



Hypopharynx of Trinoton luridum, X 245. 



A, oesophageal sclerite ; B, fused rami ; C, anterior lobes of hypopharynx ; 

 D, lateral piece ; E, maxillary fork ; F, posterior cornu. 



Trinoton luridum JST. (from the Duck). — The anterior cornua 

 have disappeared— probably fused in the central rod, which is 



