296 SIR JOHN LUBBOCK ON THE THYSANURA. 



tenent hairs. PI. XXI. fig. 2 represents one of the posterior feet. The spring is simple 

 in form (PL XXI. fig. 3). It has no tenent hairs ; and the terminal lamellae are without 

 teeth ; the hairs are simple, and shaped like a lady's riding-whip, bnt rather rough. 



S^n ntthukis luteus, n. sp. (PI. XXI. figs. 4-7.) Yellow; eyes on a black patch; 



apical portion of antennae violet. 



The females, which are decidedly larger than the males, are about -^ of an inch in 

 length. Very common, among grass, from May to July. 



In colour and in habits this species closely resembles the S. luptdince, of Bourlet ; 

 the eyes, however, are situated on a black patch. My S. aureus agrees with S. luteus 

 in the possession of the black patch, but differs in the form of the caudal lamellae, of the 

 feet, and of the antennae. 



The four segments of the antennas (PL XXI. fig. 5) increase in length from the base 

 to the apex, each being nearly twice as long as the preceding : the proportions are 8, 

 15, 24, 45. The terminal portion consists of about twelve segments more or less closely 

 -oldered together and each bearing a whorl of hairs ; the four central segments are 

 more distinctly marked than those on either side of them. At the extremity of the 



- 



some rod-like hairs 



Though the males are smaller than the females, their antennae are not only relatively, 



but absolutely longer. In form, however, there is no material difference between the 



s^xes. 



The mandibles are strong, but the terminal teeth, excepting the last of all, project 



very slightly. The teeth are four and five in number ; those of the male and female 

 are alike. 



The claws (PL XXI. fig. 6) are simple; the inner one is small; there are two tenent 

 hairs on the upperside; and the inner claw, which is elongated, appears to terminate 

 in a small globular expansion, which has probably the same function. The feet are 

 alike in both sexes. 



Caudal appendage (PL XXI. fig. 7). The basal segment tapers slightly; it bears 

 scattered setae, but no tenent hairs. The terminal lamellae are elliptical, without sets or 

 teeth. At the end of the abdomen are two setae much stronger than the rest. The 

 caudal appendage of the male resembles that of the female. 



Some specimens have on each side two longitudinal bands of rather darker yellow. 

 These, I believe, only form a variety. These specimens have three dark spots in a 

 on each side in the paler portion ; each of these bears a hair. 



It is very amusing to see these little creatures coquetting together. The male, which 

 is much smaller than the female, runs round her, and they butt one another, standing 

 face to face, and moving backwards and forwards like two playful lambs. Then the 

 temale pretends to run away and the male runs after her, with a queer appearance of 

 anger, gets in front and stands facing her again; then she turns coyly round, but he, 

 quicker and more active, scuttles round too, and seems to whip her with his antennae; 

 then tor a bit they stand face to face, play with their antenna*, and seem to be all in 



all to one nnntlmr. 



