426 PROCEEDINGS OF THE ACADEMY OF [1893. 



being the case iu both jaws in nearly all of the many specimens ex- 

 amined. 



The acetabulum resembles that of B. pulcherrima in being 

 directed veutralward. Its diameter is greater than that of the first 

 or second body segments. Bi-annulation is conspicuous on the 

 anterior four post-cephalic segments only. 



The alimentary canal is strongly sacculated in the fourth and fifth 

 segments, in the sixth is pushed to the left side by the development 

 of the atrium (this occurs in adults only), in the seventh is 

 thrown into a complete double transverse loop which passes first to 

 the right and then to the left, and finally passes directly to the anus 

 in the ninth body segment. The spermatheca is very small and in- 

 conspicuous, while the penis- sac is well developed, and possesses 

 a long vermiform appendage (atrium) which forms a loop dorsally 

 over and around the intestine. Sexual and nephridial openings as 

 in B. pulcherrima. 



In contraction the body of this species is shaped like a short- 

 handled raquet; in extention it has the outline of an Indian club from 

 dorsal and ventral views. 



Length of mature animal 5*5 mm. 



Maximum breadth, 1*3 " 



Diameter of acetabulum *5 " 



Transverse diameter of jaw "048 " 



Length of cocoon without pedicle . . . "35 " 



The cocoons resemble those of the last described species, but are 

 frequently provided with an apical fibrous tuft. They are invari- 

 ably attached (to the extent of my experience) to the palmar surface 

 of the propodite of the great chehe. The animals themselves are 

 largely restricted in their distribution to the same segments of the 

 limb, and are usually to be found in numbers clustered at the base 

 of the pincers to which position the form of the body peculiarly 

 adapts them ; for while the constricted anterior region, by reason of its 

 tenuity, easily escapes crushing between the closing limbs of the chela, 

 in which position it is frequently liable to be caught, the important 

 organs of reproduction and digestion are massed together near the base 

 of attachment, entirely out of reach of danger from this source. Fre- 

 quently they wander to other parts of the same pair of limbs, or even 

 to the two pairs of ambulatory limbs following. 



