LEPIDASTHENIA SIBOGAE. 161 



NOTE XIII. 



ON -TWO REMARKABLE SPECIES OF 

 APHRODITIDAE OE THE SIBOGA-EXPEDITION 



Dr. R. HORST. 



(With 2 textfiguros). 



I. Lepidasthenia sihogae, n. sp. 



At Station 282, off the North East point of Timor, at 

 a depth of 27 — 54 M., a single Polynoid-worm was kept, 

 that is characterized not only by the singular shape of its 

 elytra, but also by the abnormal manner of their attach- 

 ment. For the elytra have not the usual appearance of flat, 

 scale-like organs, that are attached at their under side, 

 but they are represented by small oval buds, not quite so 

 high as broad and fixed at their median side to a long 

 elytrophore ; there are 26 pairs of them, as in other 

 Lejndasthetiia-s^ecies situated on segment 2, 4, 5, 7, 9 — 23, 

 26, 29 — 65. They are quite smooth and without any ap- 

 pendages. About the internal structure of these organs *) 

 I have observed, that like in other elytra there is an 

 epidermis-layer of polygonal cells, ending at their base 

 in fine fibres, forming a dense network in the centre of 

 the organ; the presence of a nerve could not be stated 



1) My colleague Dr. H. W. de Graaf was kind enough as to make some 

 transverse and longitudinal sections. 



Notes from the Leyden Mluseum, Vol. XXXV. 



11* 



