MONOGRAPH OP THE GENUS PERIPATUS. 471 



In a male with 30 legs : 



Right side. — Legs 21 — 24 inclusive, each had one such tubercle ; legs 



25 — 28 inclusive, each had two such tubercles; legs 29 and 30 were 



without them. 

 Leftside. — Leg 21 had one tubercle; leg 22 was without one; legs 23 



and 24 each had one ; legs 25 — 28 inclusive, each had two ; legs 29 



and 30 were without them. 



In another male with 30 legs : 



Right side. — Leg 23 had one tubercle ; legs 24 — 28 inclusive, each had 



two ; legs 29 and 30 were without. 

 Leftside. — Leg 22 had one ; legs 23 — 28 inclusive, each had two; legs 



29 and 30 were without them. 



When one papilla only is present it is the distal one. 



From these examples it is obvious that the arrangement of 

 these tubercles is different not only in the different individuals 

 but also on opposite sides of the same individual. The last 

 two legs are always without them. Gaffron found precisely 

 the same irregularity in the arrangement, but in his specimens 

 they were symmetrical. In one with thirty legs, the twenty- 

 second leg had one, and legs 23 to 28 each had two tubercles. 

 While in another male with twenty-nine legs, leg 20 had 

 only one, while legs 21 to 27 each had two. The pits at 

 the apices of these tubercles are, according to Gaffron, the 

 openings of glands corresponding to the crural glands of 

 Capensis. 



The legs of the last pair are smaller than the penultimate, 

 and possess only two spinous pads. The legs of the penulti- 

 mate pair are without the nephridial opening, and the pedal 

 groove is inconspicuous as it is in the last pair. I could not 

 satisfy myself whether the legs of the last pair possessed a nephri- 

 dial opening ; but Gaffron states that they possess a nephridium. 



Gaffron (No. 35) describes a peculiar bean-shaped papilla, 

 placed in a pit of the integument on the dorsal surface of the 

 leg near the foot. Its surface is smooth as is also the lining 

 of the pit in which it is placed. It is found in the Trinidad 

 species, and may very probably turn out to be characteristic 

 of the neotropical species. 



