in the British Museum. 95 



described or redescribed several species from other parts of the 

 -norltl, which seemed to me of special interest. Owing 

 to the fact that I have taken characters from several organs 

 — for instance, the legs and antennse — hitherto more or less 

 ignored by students of this group, it has been necessary to 

 give rather long descriptions. In this paper I have no 

 occasion to discuss the generic value of several of these 

 characters, but refer to another paper which I hope to publish 

 shortly. The same is the case with my studies on the coxal 

 sac of Ch. socotrensis, sp. n., of which I have given a short 

 description without comparison with the corresponding organ 

 in other nearly related forms. With regard to the ecdysis, 

 about which scarcely anything is found in the literature, I 

 refer to the description of Ch. sculpturafus, Lewis (p. 122). 



Some cases of abnormal segmentation in Ch. sculpturafus, 

 Lewis, and Ch.javanus, Thor., described in the third part of 

 this paper, and compared with similar cases in other Arthro- 

 pods and Annelids, are, perhaps, of more general interest. 



I. — Systematic Part. 



The following synopsis of the species of the genus Chelifer 

 from the Australian Region, as well as of those from other 

 parts of the world described in this paper, has been difficult 

 to get into proper shape on account of the very incomplete 

 descriptions of many species ; but, nevertheless, I hope that 

 it will be fairly easy to identify most of the species by its 

 help : — 



a. Femora and tihise of the palps beset with large 



subcorneal tubercles sculpturatus, Lewis. 



h. Femora and tibite of the palps without any 

 tubercles. 

 a^. Femora of the palps at least three times 

 longer than broad. Fingers shorter than 

 hand. 

 «^. Trochanter of the palps distinctly broader 

 than the femur. 

 a^. Fyes distinct. Abdominal and tarsal 

 *' tactile " hairs present. 

 a*. Hairs partly clavate ; skin sha- 



greened laysanensis, Sim.* 



fc*. Hairs pointed ; skin almost smooth ; 

 tarsus iv. w ith median " tactile " 

 hair and only I'o times longer than 

 femur iv. is high. Claws with 



* Ch. laysanensis, Sim., and Ch. megasoma, Dad., each occur twice in this 

 synoptic key, because the characters used under a^-h^ and u^-b^ are not 

 mentioned in the original descriptions. 



