6 THORELL, A NEW ARACHNID. 
tyle, the claw being received in a fork formed by the pro- 
longed inner corner of the apex of the first joint, or man- 
dible properly so called: The palpi are stretehed backwards, 
under the body; their basal joint forms a true capitulum, 
which is inserted in a deep socket on the under side of the 
maxilla, and they are therefore, probably, moveable in more 
than one direction. The trochanters of the two posterior 
pairs of legs are two-jointed. It is evident, therefore, that 
the Cryptostemmoidae differ in so many important points from 
the Suborders into which the Opiliones had formerly been 
divided, that it becomes impossible to place this Family in 
any of them. By the general form of the body and the 
short legs, the Cryptostemmoidae remind one, however, of the 
Troguloidw, in the vicinity of which they have also generally 
been placed: their »hood> (>»chaperon>) represents no doubt the 
forwardly directed, not moveable part of the cephalothorax, 
which in the Troguloidew and some other Opiliones protects 
the parts of the mouth. 
The Zoological State Museum at Stockholm possesses an 
Opilio belonging to the Öryptostemmoide or RKRicinulei, which 
was captured in Sierra Leona a century ago by A. AFZELIUS. ! 
Though pinned and somewhat damaged, this specimen is suffi- 
ciently well preserved to show all the more essential parti- 
culars of its external structure. Mv first impression on exa- 
mining this animal was, that I had an example of the Crypto- 
stemma Westermanni before me; indeed the general form of 
the body, the »hood> and the palpi are almost completely 
such as are figured and described by the above cited authors; 
but the legs appear to differ materially from those of GUÉRIN- 
MEÉNEVILLE's species. He says in fact, that they are »aplaties», 
and the figures of the animal, seen from the upper side, show 
the tibiv of the 2:nd pair and the metatarsi of the 3:th pair 
dilated und flattened on the inner side, whereas in the specimen 
examined by me, none of the legs show the least trace of 
! This naturalist, born in 1750, commenced his career in the Uni- 
versity of Upsala as a »Docens Linguarum Orientalium>», but after some 
years he abandoned his philological pursuits and devoted himself to the 
study of Natural History. Having been appointed a »Botanices Demon- 
strator> in the University, he went, in 1789, to England, and lived many 
years there and in the newly founded colony of Sierra Leona, whence he 
sent home and to London valuable botanical and zoological collections. 
After his return to Sweden in 1799, Dr AFZELIUS was appointed an E. O. 
Professor of Medicine. He died in Upsala at the age of 86 years. 
