94 Mr. B, F. Ciimmings on 



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

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

 bristles also on each pleuruni behind the seventh segment. 



Measurements o/Eulinognathus denticulatus 

 [millimetre-scale) . 



Length. Breadth. 



Head -29 (at margLn) -23 



Thorax -3 -51 



Abdomen 1-2 1-05 



Total 1'79 



Length of antenna . . '25 



M A L L P H A G A. 



Family Trichodectidse. 



Described below is a curious new form belonging to this 

 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 sfiecies of mite), the main 

 features in the morphology of the skeleton have been made 

 out, although much of the chsetotaxy still remains uncertain 

 or obscure. 



They were collected on the two-toed sloth [Choloepus 

 didactylus, Linn.) in Biitish Guiana. So far as I know, the 

 only other species of Mallophaga recorded from an Edentate 

 is Gyropus hispidus, Nitzsch, from Bradypus tridactylus. 

 Among the Anoplura, the remarkable Tlybophfhirus noto- 

 phnllus (Neumann), Enderlein, a parasite of the Cape 

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

 Edentate host. 



TricJiodectes 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. 



