94 Mr. B. F. Ciiinaiings on 



lower margin. On the soft chitin, just in front of tlie first 

 pleurite, a group of eight or nine of the modified liairs. Two 

 bristles also on each pleuruni behind the seventh segment. 



Measnrementu 0/ Eulinognathus denticuhitus 

 ( millimetre-scale) . 



M A L L P H A G A. 



Family Trichodectidae. 



Described below is a curious new form belonging to tliis 

 family, which is of especial interest on account of the phjlo- 

 genetic position of its host, an Edentate. 



The material from which the new form is described, con- 

 sisting of a (^, three ? ?, and a larva, was very kindly 

 presented to the British Museum by Mr. A. J. Engel Terzi, 

 and, in spite of their poor condition of preservation (the 

 specimens had been attacked by a species of mite), the main 

 features in the morphology of the skeleton have been made 

 out, although much of the cha^totaxy still remains uncertain 

 or obscure. 



They were collected on the two-toed sloth {Choloepus 

 cfidactt/lus, Linn.) in Biitish Guiana. So far as I know, the 

 only otiier species of Mnllophaga recorded from an Edentate 

 is Gyropus hispidus, Nitzsch, from Bradypua tridnctylus. 

 Among the Anopliira, the remarkable Hybophthirus noto- 

 2)haUus (Neumann), Enderlein, a parasite of the (Jape 

 anteater {Orycteropus afer, Pall.), is the only species with an 

 Edentate host. 



Tr'ichodectes gastrodes *, sp. n. 



The new species is readily distinguished by its large 

 dimensions (see p. 100), the form of the head (see figs. 2&3, 

 p. 96), and by the chaiacter of the abdomen, which, being in 

 both male and female without tergites or sternites, is loose and 



* " The Potbellied Louse " is suggested as a popular name. 



