MOEPHOLOGT OE THE PEDIPALPI. 39 



but more likel)', as Gaubert suggests, to division of segment 3. 

 Antero-posterior motion takes place between this additional 

 segment and 3. In appendages v. and vi. a second segment is 

 intercalated in tbis region. Whether the intercalated segment 

 is connected with a borseshoe-shaped strip of cbitin wbich 

 strengthens articulation 2-3 in the Pedipal^^i or not, is an interest- 

 ing point wbicb must remain for the present unsolved. 



Pseudoscor pious . — In these minute forms the masticatory func- 

 tion has been lost, except in appendage ii. In the other limbs 

 segments 3 and 4 are fused together, their line of junction being 

 marked by a groove, while segment 7 is so reduced as to have 

 been overlooked by everyone escept Croneberg. The limbs are 

 exceptional in that the division between the ascending and 

 descending portions of the limb occurs at articulation -±-5 instead 

 of articulation 3-4. 



Acarina. — The limbs here seem to have only six segments, but 

 my researches have not led me to any conclusion as to which 

 segment is lost. Appendages i. and ii. are variously modified iu 

 connection with the modes of life of the different forms, xls 

 being a degenerate group derived probably from the neighbour- 

 hood of the Phalangidse (Bernard says from the Araueidae) they 

 need not detain us here. 



To summarize the results obtained from the above brief 

 account of the appendages, the terrestrial forms seem to dift\r 

 from the aquatic ones {Limulus and Eurypteridas) in that the 

 majority of the appendages have lost their masticatory function. 

 This confinement of mastication to a smaller area seems to me a 

 natural result of terrestrial life in such forms as these, which 

 suck in their food in a liquid form, since a contingency to 

 be by all means avoided is evidently that the juices on which 

 they subsist should dry up. Beyond this the modifications cf 

 the appendages would seem to unite the Pedipalpi, Phalangidse, 

 and Araneidae together as a natural group. The Scorpions difi'er 

 from them on one side, and Galeodes, as usual, stands alone on 

 the other, though apparently showing afilnities to the Pedipalpi. 

 The condition of things in the Pseudoscorpions points either to 

 their type of limb being independently derived from a compara- 

 tively primitive form, or to their having passed through a much 

 simplified stage, like the Acarina. I think the latter more pro- 

 bable, though I wish it to be distinctly understood that I do not 

 propose to derive the Pseudoscorpions from the Acarina. 



