272 MR. G. BEOOk's BEVISrON 01" THE 



showed that OrcJiesella cincta, L., was of such a variable nature 

 in its markings as to present almost every phase between a 

 specimen without markings and one nearly black. 



The object of the present paper is to show that in the genus 

 Entomohrya also we have a common widely distributed species 

 which, at different ages and under different conditions, presents 

 a similar series of gradations from the light to the dark which 

 have been proved to occur in Orchesella cincta, L. By the aid 

 of photography I have been enabled to arrive at this conclu- 

 sion with the more certainty, because I am always assured of 

 the accurate mapping out of the markings, where drawing to 

 be as accurate would be an extremely difBcult task. Again, 

 the camera has assisted me in the identification of certain 

 markings which, when seen under the microscope and by gas- 

 light, did not appear at all. 



Entomobrta, Bondani. 



1839. Isotonia, Bourl. (in partem). 

 1842. Degeeria, Nic. (in partem). 



Mesonotum not prominent ; fourth abdominal segment at 

 least as long as the three preceding taken together. Eyes 

 eight in each group. Antennae shorter than the body, consisting 

 of four segments and a minute basal ring ; the three terminal 

 ones subequal. Eeet biunguiculate, each claw with a tenenthair. 

 Upper claw usually with two teeth — one, well marked, about the 

 middle of the inner margin, and the other smaller or sometimes 

 absent. There is sometimes a small tooth on the outer margin. 

 The number of the teeth seems to vary considerably in the same 

 species, so that this character is of no specific value. Saltatory 

 appendage long. 



Body covered with long hairs which are clubbed on the an- 

 terior part of the body, and long and geniculate on the posterior 

 part. Besides these there is a thick downy covering of fine 

 short hair all over the body. 



1. Entomobeta nivalis, L. 



\']A(}. " SmS grS insekter," &e., De Geer, Vet.-Akad. Hand. vol. i. 



p. 276. 

 1758. Podura nivalis, L. Syst. Nat. ed. x. t. i. p. 609. 

 1836. P. nigromaeulata, Temp. Thy. Hibern. p. 94. 

 1838. P. minuta, Burm. Handb. d. Ent. B. ii. p. 449. 



P. nivalis, Burm. ibid. p. 450. 

 1858. Degeeria pi, Herklots, Tijds. v. Entom. vol. i. p. 94. 

 1862. D. nigromaeulata, Lubk. Notes Thy. pt. ii. p. 593. 



