54 Transactions. — Zoology. 



prominent ; the cheeks bristly m the upper half ; the fronto- 

 orbital seta? do not extend much below the base of the 

 antennae The second joint of the antenna? is not much 

 elongated ; the third is about one and a half times the length 

 of the second, and reaches rather more than halfway to the 

 epistome. The abdomen is ovate, and has no macrochaetae 

 on the middle segments. The first posterior cell is open, and 

 ends before the tip of the wing ; the fourth longitudinal vein 

 curves sharply round to an acute angle with its former direc- 

 tion, and then curves outwards more gently ; the last section 

 of the fifth longitudinal is between one-fourth and one-fifth 

 the length of the previous section. 



1 place this species with great doubt in Tachina. 



Genus Proscissio, gen. nov. 



Head much produced and wedge-shaped in front, the 

 frontal band deeply grooved ; but the head is not much 

 longer at the base of the antennae than at the vibrissas. Eyes 

 small, about half the length of the head, bare or nearly so. 

 Antennae rather short, but reaching more than halfway to 

 the epistome ; the third nearly three times the length of the 

 second. Second joint of the arista longer than broad ; the 

 third joint minutely pubescent. Frontal bristles in a single 

 row in both sexes, not descending below the bases of the an- 

 tennae. Cheeks and facial ridges bare ; vibrissas only slightly 

 above the anterior edge of the mouth. Proboscis and palpi 

 long. Abdomen oblong, the middle segments with a pair of 

 discal setae. Wings without any couspicuous seta on the 

 costa, but sometimes one of the short bristles near the end 

 of the auxiliary vein is rather longer than the others ; fourth 

 longitudinal vein usually bent sharply at a right angle and 

 then curved gently outwards ; the first posterior cell is open, 

 and ends a little before the tip of the wing ; the posterior 

 cross-vein is nearer to the margin than to the chief cross- 

 vein ; and the last section of the fifth longitudinal is about 

 one-fifth of the length of the preceding section. 



The small eyes and prominent forehead are sufficient to 

 distinguish this genus from Tachina. 



Key to the Species. 



Second joint of the antenme pale-brown . . P. modica. 

 Second joint of the antennse dark-brown. 

 KneeR black. 



Thorax with white tomentum . . . . P. cana. 



Thorax with yellow tomentum .. .. .. P. valid a. 



Knees tawny . . . . . . . . P. montana. 



Proscissio cana, sp. nov. 

 Head brown, with grey tomentum on the face. Antennae 

 dark reddish-bown, the third joint with grey tomentum. 



