152 



FRED. V. THEOBALD. 



equal in length, reaching to the coxae of the second pair of legs. Legs very short and 

 thick, the tibiae a little shorter than the femora, equidistant apart ; claws double 

 on each leg, no hairs visible. There are traces of darkness on the head of varied form 

 in balsam preparations (but no rows of dark spots down the abdomen) and thin 

 hairs. Cauda dusky, shghtly hairy. Length, l'8-2 mm. 



Egypt : Gizeh, 30.iii.09 [F. C. WillcocJcs). Also in Europe. 



Food-plants. Wheat and various grass roots. 



The structure of the apterous Egyptian specimens agrees with Buckton's Tthizohius 

 graminis, which he described first as Rhizobius poae. The apterae do not show the 

 black spots referred to by Buckton nor does Mr. Willcocks refer to them ; but as the 

 structure agrees exactly I feel sure the Egyptian species is the same as the European. 

 Nevertheless I place it with a query. Alate Rhizobius have not so far been described, 

 so that the winged viviparous female detailed here is the type of that genus. 



Fig. 38. Bhizohius graminus^ Buckt. ; 



A, under surface of head of apterous ? ; a, h, antenna. 



B, head and antenna of alate $ ; (i) ocellar process ; (ii) basal antennal 



segments ; (iti) apex of 6th segment ; (iv) sensorium on 5th ; C, proboscis ; 



D, Cauda and anal plate ; E, wings ; F, abnormal lower wing. 



Some of the specimens sent by Mr. Willcocks came from grass roots along a canal 

 bank at Gizeh, the others from the roots of wheat. 



Buckton describes the apterous female as " dull ochreous yellow. Eyes, antennae, 

 legs and 2 occipital longitudinal bands, brow^n. Abdomen deeply ringed with 

 numerous dark spots, ranged in transverse rows across the dorsum. A pale hne 

 passes from the vertex down the whole back." Buckton refers to the front tarsi 

 as having a single claw, evidently in error. Willcocks describes the nymph as " yellow, 

 wing-buds pale, eyes and ocelh red. Legs and antennae very pale smoky." 



The females, larvae and pupae produce long filaments of a bluish-white secretion, 

 like wool, from pores on the dorsum. 



A second species seems to have been found by Willcocks in which the body is very 

 globose and covered with numerous short hairs, farinose and buff in colour, and 

 possibly a third species, but I am unable to isolate these. 



