CRAYFISHES. 355 



it is true, from Philippi's figures of P. spinifrons, at least from the copy of those 

 figures in Dr. Ortmann's possession, in some respects, for instance the rostrum 

 is shorter and broader and the immobile finger of the large claw is much longer. 

 These discrepancies may be due to the inaccuracy of the original figures or of the 

 copy of these figures which is all that I have before me. Philippi's diagnosis, 

 moreover, takes no account of the pronounced asymmetry of the chelipeds, a 

 marked feature of the specimen from the Paris Museum. I append a description 

 of the latter; future explorations in Chile will determine whether it is the same 

 species as PhiUppi's. 



Cephalothorax subcylindrical, smooth, shorter than the abdomen; areola 

 broad, considerably less than one half the length of the anterior section of the 

 carapace ; rostrum triangular, reaching to the distal end of the second antennu- 

 lary segment, upper surface plane, with slightly elevated margins; post-orbital 

 ridges obscurely marked except anteriorly where they form an elongate, low, 

 tubercle without an acute spine; the antero-lateral angle of the carapace is 

 produced to a prominent blunt angle below the orbit; there is no lateral or 

 branchiostegian spine. The abdominal pleura are broad, with rounded angles. 

 The antennal scales are broad, broadest in the middle; lower surface of the 

 peduncle of the antenna hairy ; epistoma triangular, anterior angle acute ; third 

 pair of maxillipeds clothed with dense hair below. Chelipeds unsymmetrical, 

 the right one being much the larger, meros pretty smooth, except on its lower 

 face which is provided with a row of small marginal tubercles and clothed with a 

 heavy coat of hair; the superior margin of the meros is destitute of a spine; 

 the carpus has a deep longitudinal groo\'e along its external face; below this 

 groove the surface is smooth, alcove it there are small sriuamous tubercles which 

 on the superior border of the carpus assume the form of prominent tubercles, or 

 blunt teeth, four or five in number; the infero-interior face of the carpus of the 

 larger cheliped is likewise furnished with similar tubercles; the right (larger) 

 claw is very thick, with rounded superior and inferior borders; the body of the 

 claw is beset with flattened low tubercles which are most pronounced anteriorly, 

 near the socket of the dactylopodite ; the fingers gape, are pitted in place of being 

 tuberculated, and there are about three blunt teeth on the cutting edge of each 

 finger, one of which is especially prominent; both fingers are heavily bearded at 

 the base, especially on the inner side; the left (smaller) claw is nearly smooth, 

 with long and slender fingers that meet throughout their length, destitute of 

 teeth liut furnished with a beard at the base, like the larger claw. Inner branch 

 of the last pair of abdominal appendages armed with a submarginal spinule at 



