MR. a. BROOK Olf A FEW GENTTS OP COLLEMBOLA. 543 



SiNELLA, nov. gen.* 



Head quite as broad as long, a little protruded between the antenns. 

 Eyes situated near the base of the antennae, four in number, two on each 

 side, each lens situated on a separate patch, the upper one rather larger 

 than the lower and irregular in outline. AntenncB composed of four seg- 

 ments with a rudimentary fifth as in Degeeria : first longer than is usual 

 in Degeeria, about one third the length of second; second usually a little 

 longer than third ; fourth about twice as long as third : proportional 

 length of segments varies, however, a little in different individuals. 

 Prothorax small, entirely hidden by the mesothorax above. Mesothorax 

 large, nan-ower anteriorly. Metathorax shorter than the second. First 

 abdominal segment quite small, difficult to see in some specimens, unless 

 the insect is laid on its side. Second abdominal segment about three times 

 as long as first. Third abdominal segment twice as long as second ; be- 

 low produced posterioi'ly under the fourth for half its length. Fourth 

 abdominal segment nearly as long as the thorax and first three segments 

 of the abdomen taken together, tapering slightly posteriorly. Fifth and 

 sixth abdominal segments small. Spring always reaching the ventral tube, 

 which in the living insect is usually clasped by the terminal segments. 

 Manubrium about as long as the denies, scarcely tapering. Denies tapering, 

 slightly crenate along the margin and corrugated across as in Degeeria ; 

 towards the extremity each of the dentes splits up into three parts, the 

 outer two of which seem to form a sheath, ciliated along their margins ; the 

 inner one bears the mucrones. Mucrones, seen from above, almost straight; 

 seen laterally, scimitar-shaped, consisting of two lobes. Claws of first pair 

 of legs — Large claw curved, and beai-ing a large tooth about the centre of its 

 inner margin, and two small ones between that and the tip ; sometimes 

 the small teeth are very indistinct, and only appear as an unevenness in the 

 margin. Lower claw spathulate, about half as long as the upper one, and 

 without teeth : there is no tenent hair properly so called ; but its place is 

 taken by a strong hair of the ordinary kind. The head and thorax are 

 thickly covered with bristles, which are bent forwards on the head and out- 

 wards on the thorax ; they get gradually thicker towards the tip, when 

 thev suddenly come to a point ; finely ciliated along the margin. Ter- 

 minal segment of the abdomen covered with short thick clubbed bristles, 

 which are bent inwards and strongly ciliated. 



It will be seen from tte above description tbat the species here 

 described, and for v^hich I propose a new genus, differs from all 

 other described species of CoUembola, the IsototJia qicadrioculata 

 of Tullberg excepted, in having two eye-patches on each side. 

 From the genus Degeeria of Nicolet, to which perhaps it is nearest 

 allied, it differs in the following points : — 



* I have named the genus after Mr. J. Sinel of Jersey, who has been very 

 assiduous in the collection of specimens of CoUembola for me. 



LINN. JOTJEN. — ZOOLOGT, VOL. XVI. 40 



