YELLOW, AND BLACK, SPRTNGTATLS. 118 



The colour was pale yellow, or sometimes inclining to a more 

 orange tint. Length variable, but about (or commonly less than) the 

 thirty-second of an inch. Head with eyes on a black patch. Antenna? 

 four-jointed, each segment being (as mentioned by Sir J. Lubboclc) 

 nearly twice as long as the preceding. The terminal segment, when 

 it had lain for some time in glycerine, and was examined by a high 

 power, appeared to be composed of twelve rings, the four lowest 

 soldered together, but slightly segmented, especially between the second 

 and third ; the following five rings distinctly segmented, smallest at 

 the base, and enlarged at the top of each with a few very noticeable 

 somewhat aborted hairs, and the terminal beads, which might be 

 considered either as three, or as two with a cross marking, more or 

 less soldered together, and lessening to the apex. In some specimens 

 the open beading scarcely showed at all. This appeared to depend 

 very much on the condition of the specimen and the fluid used for 

 examination. The terminal lamellfe of the branches of the springing- 

 fork were elliptical, in a moulted-off skin almost oblong.* 



Specimens of the black kind of Springtail, mentioned by Mr. Iron- 

 side as being observed together with the yellow kind, might be 

 conjectured to be the Smijnthums niger figured at p. 110, but of these 

 I did not receive specimens, and therefore cannot be sure. 



The genus of Snnjnthurus, with about twenty-one other genera 

 included in the division of " Springtails" by Linnfeus, and now 

 divided into ColJemhola and Thysanura, are doubtfully classed as true 

 insects. They resemble insects in being possessed of a distinct head 

 furnished with antennte, or horns, commonly with mouth-parts much 

 like those of biting insects ; of a thorax with three pairs of legs, 

 and of an abdomen, globular or linear as the case may be. But 

 besides many other points unnecessary to enter on, they di/f'er from 

 typical insects in never possessing wings, and also in often (jiot alwaj/s) 

 possessing an apparatus known as the leaping-fork, which may be 

 generally described as much resembling a pair of compasses, with an 

 enlarged longish top, and with the legs sometimes fine and straight, 

 and tapering gradually to the minute lamella or appendage at the tip, 

 sometimes variously thick and curved. This apparatus, when at rest, 

 is doubled forward beneath the abdomen, but can be suddenly unloosed 



* The only other of the eight British species of Simjnthurus to which the speci- 

 mens sent might appear on slight examination possibly to belong was the S. aureus, 

 Lubbock. But on careful examination, I did not find that the samples sent me 

 were pale below, nor did I detect a double black spot in front of the antennje, nor 

 was the terminal joint of the antennse with no distinct evidence of segmentation, 

 which is the case with aure^is, nor did the form of the two branches of the leaping- 

 fork, and of the lamellfe at the end of each branch, correspond with the figures 

 given by Sir J. Lubbock of those of S. aureus. 



