C(ELIOXYS. 609 



Head transverse, about as wide as the thorax, or in some 



species wider ; eyes pubescent 

 ocelli in a triangle on the vertex 

 antennae filiform ; labial palpi 

 4-joluted, basal two joints elon- 

 gate, the 2ud somewhat longer 

 than the 1st, apical two minute, 

 articulated at an angle near 

 apex ; maxillary palpi 3-jointed, 

 basal joint shortest, the 2nd 

 Fig. 171. —Ceelioxi/sbasalis, 2- f thicker, apical joint ovate : la- 



brum elongate, the sides nearly 

 parallel, base broad and produced at the lateral angles. Thorax 

 short, more or less globose, the scutellura with a lateral curved 

 tooth at base ; fore wing with an elongate radial cell subacute 

 at apex ; two cubital cells subequal in length, the 2nd receiv- 

 ing the two recurrent uervures at base and apex respectively ; 

 the 1st transverse cubital nervure oblique, the 2nd angled and 

 bent inwards ; legs feeble, slight. Abdomen somewhat elongate, 

 conical, the base truncate, acute at apex ( $ ), obtuse dentate ( d" ). 

 The male has also the anterior coxae toothed and the claws bifid. 



The species of Coeliox>/s are parasitic in the nests of 3Iefjachile. 

 I have often watched G. hascdls alight near the nest of Mega- 

 chiJe Janata, while the latter was working, remain perfectly still 

 until the 2Ier/acJiile had gone off to collect fresh pollen, then slip 

 in, turn round, and poke its big head out of the entrance to the 

 nest, which it fairly blocked. Sometimes the Cielioxys departed 

 before the Megadiile had returned, but occasionally remained in 

 the nest with its head blocking up the entrance, and for a long 

 time kept the rightful owner at bay on her return to the nest. 



Key to the Sjiecies. 



Females. 



A. Ventral plate of apical abdominal segment 



more or less spoon-shaped. 



a. Scutellum long, subangular in middle 



posteriorly C. deeipiens, p. 510. 



b. Scutellum short, broadly arched in middle 



posteriorly. 

 a'. Second and third abdominal segments 



with deep transverse grooves C.fuscipennis, p. 511. 



h' . Second and third abdominal segments 



not grooved C anyidatus, p. 511. 



B. Ventral plate of apical abdominal segment 



conical, more or less acutely pointed. 



a. Head with ricli fulvous pubescence C. ducalis, p. 512. 



b. Head with snow-white pubescence. 

 a' . Under 9 mm. lonp. 



a^. Front with a medial vertical carina . . C. minutus, p. 512. 

 6^ Front not carinate C. capitatus, p. 512. 



