172 MB. D. SHARP ON THE EESPIBATOET 



concealed under a stone and quiescent. This observation ceased 

 at 5.45 P.M. 



No. 2. Same date. — Observation commenced at 9.19 p.m. by 

 artificial light. At 9.31, was swimming about with great activity, 

 but apparently did not rise for breath ; aind the same things 

 occurred at 9.40 and at 9.44, but apparently no breathing. Ob- 

 servation ceased at 10 p.m. I am sure the movements were 

 deranged by the light : the specimen was placed in the dark after- 

 wards, and on being visited was seen swimming about, but 

 speedily took refuge; these results were again repeated on a 

 second visit. 



This insect is a powerful swimmer ; when placed on its back it 

 uses the front legs with a pawing motion, and strikes out with the 

 hind ones, the latter being generally used simultaneously, but 

 occasionally one after the other. It runs on a dry surface rapidly, 

 trailing the hind legs. 



No. ,3. Sept. 26th. — The same male beetle, concealed; obser- 

 vation continued for one hour, during which the beetle was quite 

 quiescent and never appeared. 



No. 4. At night, by lamplight. — At 9.11 p.m. watch begun, when 

 the beetle came out from concealment at the subjoined times, but 

 did not rise. 



9.24 

 9.35 



9.40 

 9.45 



9.50 

 9.53 



10. 4 

 10.10 



Further observation ceased at 10.11 p.m. Thus the beetle did 

 not rise to breathe, though it kept coming out from concealment 

 as if to do so ; its movements were perhaps disturbed by artificial 

 light. 



Summary. — This species is closely allied to H. elegans ; and it 

 would appear that, like it, it is often very active and breathes very 

 seldom, and very rapidly. 



IX. NOTEEUS SPARSUS. 



No. 1. Sept. 26th. — In this case my observation commenced at 

 1.31 P.M., beetle concealed at edge of a piece of wood ; at 2.23 it 

 crawled up this wood to the surface, breathed for 8 seconds, 

 and returned to its original position. Observation ceased at 

 2.31 P.M. 



No. 2. Hesumed watching the same night, with the appended 

 results : — 



