60 



MR. L. A. BOREADAILE ON THE 



and third segments. In many Decapoda, as in Leander (text- 

 fig. 46) the same fact is clear upon careful examination. I shall 

 call the processes in question the inner and outer lacinice. The 

 outwardly-directed lobe which is often present upon the first 

 segment has been regarded by various authors as the exopodite, 

 and the conclusion drawn that the part of the limb proximal to 

 the basipodite is lacking. It is hard to see upon what evidence 

 this view can be based. The exite is much more easily inter- 

 preted as a proepipodite. It is represented in Leander by a hump 

 upon the base of the first endite. 



Text-figure 40. Text-figure 41. 



Text-figure 42. Text-figure 43. 



Text-fig. 40. End view of left mandible of Conchodytes tridacnte. 



„ 41. End view of left molar process of Periclimenes sjpiniferus. 

 „ 42. Oblique view of end of right molar pi'ocess of the same species. 

 43. Same view of right molar process of Saron marmoratiis. 



The two cleft lobes usually known as the " lacinia? " of the 

 maxilla (text-figs. 14-17) are each equivalent not, as has some- 

 times been supposed, to one of the elementary segments of the 

 limb, but to two, and thus they together represent the first four 

 endites of the primitive limb.' This interpretation is strongly 

 suggested by such appendages as the maxilla? of larval Penseides 

 (text-fig. 16) and especially by that of Cerataspis (text-fig. 15), 

 and is not contradicted by the fact that articulations are often 



