110 HYDROCAMPA STAGNATA. 



spiracles behind these are very small, flat, and brown, 

 yet can just be detected with a lens. (William 

 Buckler, 11th September, 1877 ; E.M.M., October, 

 1877, XIV, 97—103.) 



ACENTROPUS NIVEUS. 



Plate CLII, fig. 2. 



On the 21st of July, 1874, I received from Mr. W. 

 C. Boyd, of Cheshunt, a bottle containing, with other 

 aquatic pupse and larvae, several pupse similarly spun 

 up in silken cocoons between small pieces of stem and 

 leaves of water-thyme, Anacharis alsinastrum. 



The cocoon is about four lines in length, of a dirty 

 whitish colour externally, marked or blotched irre- 

 gularly with brown; but when this is scraped off a 

 pearly white inflated envelope remains. 



The pupa lying within is three lines long and one 

 line in diameter, tolerably equal in bulk throughout, 

 although it has the usual contour of lepidopterous 

 pupae in general. The wing-cases and antenna- and 

 leg-covers lie close to the body, and are long in 

 proportion. The head, eyes, and thorax are as usual, 

 but the spiracles are remarkable. They are three in 

 number on either side of what would be in the larva 

 the sixth, seventh, and eighth segments, and project 

 a little, like the trunnions of a piece of ordnance. The 

 anal tip appeared, through a strong lens, to have two 

 minute short bristles, and a circlet of them, few in 

 number, round the ridge of the thirteenth segment. 



In colour it reminded me of the pupa of Hepialns 

 hamuli, though paler than that species. It was of an 

 ochreous-yellow colour, brown on the thorax and 

 head; the eyes dark brown; the under-side of the 

 abdomen was paler than the wing-covers, which were 

 themselves rather paler than the back of the abdomen, 

 which was tinged lightly with orange-brown ; the 

 spiracles were brownish-orange, surrounded with a 



