MAEINE WOOD-BORING ANIMALS. 



403 



any trace of serration. On each side the border is produced as 

 a long filament which extends beyond three or four segments in 

 front. The stalk is minutely roughened and, in the specimen 

 measured, nearly five times as long as the width of the distal 

 part. The siphons (text-fig. 11) are adherent for at least five- 

 sixths of their length in preserved specimens. 



The largest complete specimen is about 30 cm. long in the 

 preserved state (excluding the pallets). The valves measure 

 12-5 mm. in length by 11-5 mm. in depth. Tlie pallets are about 

 46 mm. lono-. 



Text-figure 1 1 . 



Xylotrya capensis, sp. n. Syiitype fi'om Simon's Town. 



Siphons and associated stvuctnves from left side. The fleshy collar 

 has been divided and reflected, the pallets remaining attached. 



Remarks. — In the structure of the pallets, especially in the 

 elongated peduncle, the broad, closely-set segments, and the long 

 lateral filaments into which they are produced, this species difl'ers 

 from all those of which I have seen specimens. Blainville's 

 description of the pallets of X. pennaiifera, with the segments 

 " pourvues de chaque cote d'un long cil " suggests a comparison 

 with our species. Specimens in the Museum collection referred 

 to X. pennatifera, however, differ widely, having the segments 

 but little wider than the stalk and bearing a fringe of fihiments 

 in place of the striated membranous border. 



Proc. Zool. Soc— 1920, No. XXVII. 



