116 



DK. J. D. F. GILCHEIST ON LAEVAL AND 



Distal end^of second walking-leg of 

 Pliyllosoma of ^36 mm. X 25. 



the pleurobranch and arthrobranch 

 will be described in more detail in 

 connection with those o£ the pueru- 

 lus, in relation to which they are o£ 

 importance. It is of interest to note 

 that this and the succeedin o- legs are 

 terminated by a claw of a sub-chelate 

 type_, the last joint being bent over 

 against the preceding (fig. 31). 



There are w^ell-developed exopo- 

 dites on all o£ the pereiopods except 

 the fifth, where there is a very small 

 rudiment; this rudiment, like the 

 rudiment in the third maxillipede, 

 resembles the vesicular structure 

 which represents the first appear- 

 ance of a gill, and suggests that the 

 exopodite may represent a modified 

 gill. The third segment of the fifth 

 pereiopod is relatively long. 



The pleopods are present and well 

 developed ; their exopodites and 

 endopodites are about equal in size, 

 and in the latter is an appendix 

 interna devoid, however, of setse and 

 hooks. 



The two chief spines on the upper 

 surface of the telson are present, 

 and the margins of telson and 

 uropods are markedly denticulate. 



The Rev. T. R. R. Stabbing (6) to 

 whom, some years ago, I submitted 

 a specimen very similar in general 

 appearance and size, compared it 

 with Phyllosoma longipes, Milne 

 Edwards (5), and a pliyllosoma 

 described by Claus (3), and pointed 

 out certain differences between 

 them. That it is a stage in the life- 

 history of Jasus lalandii can only 

 be fully determined by a more 

 complete series of specimens con- 

 necting it with the " puerulus " 



