Mr. J. "W. Slioebotham's Notes on CoUemhola. 65 



as the bo ly, filiform; fork developed." Succeeding authors 

 have accepted this genus, and most*, including TuUberg 

 (1872), p. 42, Lubbock (1873), p. 129, Borner (1901), p. 63, 

 Carpenter (1906), p. 41, and Linnaniemi (1912), p. 232, 

 give as one of the characters the presence of six eyes on each 

 side of the head. I have examined three species of Orchesella, 

 and have been able to find eight in each of them. It is true 

 that two of them are mucii smaller than the rest; but if the 

 insects are treated with caustic potash and examined, the full 

 number will be observed. I give illustrations (PI. III. 

 figs. 6-8) of the eyes in the three species I have had the 

 opportunity of examining, viz. 0. cincta, 0. villosa, and 

 O. Jiavescens. In a paper on Hertfordshire Apterygota, 

 Mr. Collinge and myself (1910), pp. 118, 119, gave as 

 characters of 0, cincta and 0. viliosa : " Eyes, 8 on each side 

 of the head." 



Orchesella anomala (Carp.), mihi. 

 Entomohrya anomala, Carpenter, (1906) pp. 40-42, pi. ii. figs. 8-15. 



In June 1905 Prof. Carpenter collected some springtails 

 from Fair Head, Co. Antrim, and in 1906 described them as 

 a new species of Entomohrya of somewhat aberrant type, 

 because of the relatively short fourth abdominal segment and 

 the presence of six distinct segments in the feeler, tliese being 

 characteristic of the genus Orchesella. Prof. Carpenter was 

 under the impression tiiat Orchesella possessed only six eyes, 

 and retjarded the extreme reduction of the two hinder median 

 ocelli (Guthrie's G aiid 11) in E. anomala as being an 

 approach towards Orchesella. Having shown above that 

 eight is the normal number of eyes, i include Carpenter's 

 anomala in Orchesella. 



Another character by which the two genera may be sepa- 

 lated is by the end-knob of the antenna, this being })resent in 

 Kittomohrya, but absent in Orchesella (see figs. 2, 3). 



The presence of (so-calleil) 6-scgmented antennse has been 

 given as a feature of the geims Orchesella. This is only 

 partially correct, for young specimens have 4-jointed antennae, 

 but as they grow older the first two joints each divide into 



* Since writing' the above, I have obtained a copy of a paper \>y 

 Guthrie (1006) on the Collembolan ej'e, in which (p. 240) he gives the 

 correct number of eyes. He also sujrgests that the individual ocelli are 

 probably homologous in all the diti'erent species, and that they are 

 arranged more or less in a certain pattern, somewhat iu the shape of the 

 letter S- He has aj>signed letters A-H to the eight eyes, and 1 have 

 lettered them in the same order in my illustration of the eye-spot of 

 Orchesella villosa. 



Ann. cC- Mag. N. Hist. Ser. 8. Vol. xiii. 5 



