8. J. MC'iNTIRE ON PODUR^. 75 



to remove him and prevent the escape of the rest at the same 

 time would be impossible. 



Three other genera of the Podm-idas are alluded to in the learned 

 papers from which I have drawn so much information, viz. : 

 Orchesella, Podura, and Achorutes. 



The antenniB in Orchesella are long and six-jointed, and the eyes 

 six on each side, arranged in the form of the letter S. 



Podura and Achorutes are nearly related. The antennae in both 

 genera are short and four-jointed, and the eyes eight on each side. 

 The distinction consists chiefly in the saltatory appendage. In 

 Achorutes it is extremely short, and in Podura it is of moderate 

 length. Also, I notice that in Podura the single tenent hair on 

 each foot, which, I think, Tufifen West was the first to notice and 

 represent with his inimitable skill in the paper on the Feet of 

 Insects, in the " Linnean Transactions," and which appears to be 

 common to Podur^e generally, is absent, though it is very conspicu- 

 ous in Achorutes. The last excursion party to Hampstead may 

 remember taking some specimens there on the surface of the pool, 

 which yielded Conochilus and Volvox so abundantly. These were 

 Podura Aquatica. 



Achorutes frequents old trees, damp walls and cellars, hotbeds 

 and flowerpots, where decay is proceeding rapidly. A very dark 

 purple species, often seen in wine cellars, in Achorutes purpurescens . 

 Another species (^Achorutes armatus), of a grey colour, is said to 

 be common on stagnant water. It thus appears from my own 

 observations that scales, perfectly distinct in character, are found 

 on the genera Degeeria, Templetonia, Macrotoma, and Lepido- 

 cyrtus ; each of them, when properly displayed, being an object of 

 great beauty; and that Isotoma, Podura, and Achorutes are with- 

 out scales — at least, in all cases that have as yet come under my 

 observation. 



As no specimens of Orchesella have presented themselves to my 

 notice yet, I am doubtful as to this genus. 



Mr. Ketteringham brought me a Podura scale last summer, 

 which differs in shape and size from any I have yet seen : the 

 form is far more regular, being always ovate, and the markings are 

 very coarse, but somewhat like those of Templetonia. The insect 

 was given me at the same time as the slide of the scales, but I was 

 unable then to identify it ; I, however, strongly suspect it was a 

 species of Templetonia. 



