210 FUNAFUTI ATOLL. 



appears slightly depressed, and thus stands out very distinctly. It 

 is crossed by a numerous series of close set epidermal ridges, which 

 may even extend continuously across the dorsal cord. Laterally, 

 the ridges may either stop short at the epidermal lines, or may 

 pass across them to become continuous with the annulations of 

 the ventro-lateral body wall. These latter are invariably inter- 

 rupted at the ventral nerve cord. 



In P. flava, Willey has also recorded the existence of two 

 dorso-lateral bands in the tail region, but as he describes them, 

 these bands, which are visible externally do not cause any 

 interruption in the annulations or islets of the integument, 

 and in fact are probably only the ciliated bands of the intestine 

 showing through the epidermis by transparency. 



Behind the termination of the epidermal lines the tail gradu- 

 ally narrows to its posterior end. In this posterior region the 

 epidermal annulations may, in some specimens, be partly broken 

 up into small islands. The annulations of the tail region are, on 

 the whole, more regular than those of the branchio-genital region. 



In Part II. I propose to describe and figure the salient features 

 in the internal anatomy of this species. 



