ELYTROPHORA. 83 



two-jointed, joints subequal, without wings. Caudal 

 rami tolerably large. Antennules two - jointed. 

 Antenna3 uncinate. Mouth-organs somewhat similar 

 to those of Caliyus. Thoracic legs, four pairs, all 

 biramose. In the first pair both rami two-jointed ; 

 both rami of the second and third pairs three-jointed, 

 but in the fourth pair, while the outer ramus is three, 

 the inner is only two-jointed. 



Male. Somewhat similar to the female, but rather 

 smaller. 



1. Elytrophora brachyptera G-erstaecker. 



(Plate XIX, fig. 10; Plate XXIII, figs. 1, 2; Plate 

 XXXI, figs. 1-6.) 



1853. Elytrophora brachyptera Gerst. (48) p. 60, pi. iii, figs. 1-14. 



1863. Arnseus thynni Kroyer. (71) p. 157, pi. viii, fig. 5 a-g. 



1865. Elytrophora brachyptera Heller. (58) p. 189, pi. xvii. 



1896. Elytrophora brachyptera Bassett- Smith. (6) p. 12, pi. iv, fig. 3. 



Female. Carapace orbicular, scarcely equal to half 

 the entire length of the animal, or as 5 to 11. Frontal 

 plates distinct, without lunulae. The fourth thoracic 

 segment carrying two small dorsal plates which are 

 somewhat widely apart in front, but gradually 

 approach each other behind ; their outer margins 

 incurved, and the posterior margins, which are 

 rounded, slightly overlapping the anterior edge of 

 the genital segment. Genital segment ovate and 

 moderately tumid, nearly half as wide as the carapace 

 and about one and a half times longer than broad, 

 the lateral margins slightly arcuate, and the postero- 

 lateral corners produced into short rounded lobes. 

 Abdomen biarticulate, narrower than the genital 

 segment, first joint with the postero-lateral corners 

 somewhat produced and rounded, anal segment sub- 

 orbicular with a minute posterior lobe in the median 

 line ; caudal rami obovate, expanded towards the distal 

 end, and bearing four or five apical plumose setae. 



Antennules small. Antennas strongly uncinate. 

 Mandible and maxillae somewhat like those in Trebius. 



