232 



On a new Species of Thaumastocheles. 



which, in Th. zaleucus, seems to be in series with the ven- 

 trally directed row, though it is larger than its neighbours 

 and a little more inclined than they are. 



The specimens described by Doflein and Miss Rathbun are 

 identified with the species here described not only on account 

 of the locality whence they were obtained, but also because 

 the figures given by these authors show the teeth of the 

 larger chela arranged as in the St. Andrews specimen. It is 

 to be noted, however, that Doflein's figure shows the palm of 

 the smaller cheliped to be more than half the length of the 

 fingers. If this be correct, the character in question should 

 be omitted from the specific diagnosis, or qualified by the 

 words " in the female." In Doflein's figure, also, the smaller 



II. 



Diagram (not drawn to scale) showing 1 arrangement of teeth on finger of 

 large cheliped : I. Thaumastocheles zaleucus ; II. Th. japonicus. 



chela is nearly straight, as it is in the type of Th. zaleucus, 

 while in the St. Andrews specimen of Th. japonicus, as in the 

 photograph given by Miss Rathbun, the immovable finger is 

 bent outwards so as to form an obtuse angle with the palm. 

 In both species the last pair of perseopods are minutely but 

 perfectly chelate. This character is apparently not confined 

 to the female sex, as Spence Bate suspected it might be, 

 since Doflein states that in the male specimen examined by 

 him " Die Pereiopoden sincl vollkommen wie nach der 

 Beschreibung von Bate beim ? ." 



In the female of both species there is, on the sternal surface 

 of the thorax, between the bases of the penultimate pair of 

 legs, a trilobed structure which, from the analogy of the 



