Herbert L. Ho/wldns — On Lanieria of Duncan. 201 



between the plates are not very clear, but suffice to show that there 

 are five large genital plates, each perforated by a large pore, and five 

 small ocular plates minutely perforated. The madreporite is broken, 

 but was central and apparently prominent, restricted, as usual, to the 

 right anterior genital. The whole apical system is typically that of 

 a Cmiholectypus. 



The periproct is oval, and, although below the ambitus, is situated 

 well up on the test, being inclined at an angle of about 45° from the 

 horizontal. The outline is sharply pointed at both the adoral and 

 adapical ends, the latter being slightly the more acute. 



The peristome is small (compared with that of the Holectypin^) 

 and apparentlj^ quite circular. jS'o indication of branchial slits can 

 be seen, but the margin of the aperture is not very clearly exposed. 



A. Diagram of adapical part of amb. iii of Lanieria lanieri [B.M. E. 4572]. 



B. Diagram of adoral part (not quite reaching to peristome) of amb. iv of 



Ccenholectypus cubcB [B.M. E. 11516]. 

 The numbers refer to plates, counted from the ocular margin. 



The ambulacra are straight and narrow. The pores of each pore- 

 pair are slightly inclined perradially and adorally. Towards the 

 peristome the pore-pairs become triserial in arrangement, but they 

 seem to recover something of their uniserial plan when quite near the 

 peristome margin. There are about four ambulaeral plates to each 

 interambulacral on the adapical surface, and apparently throughout. 

 Only eight or nine primary ambulacrals intervene between the 

 oculars and the ' crushing-point ', and the full degree of crushing is 



