u 



THE ATLANTIC. 



[chap. I. 



Fig. 3 

 pellum 



The male of Scalpelliim regium (Fig. 3) is the simplest in 

 structure of these parasitic males which have yet been observed. 

 It is oval and sac-like, about 2 mm. in length by 

 9 mm. in extreme width. There is an open- 

 ing at the upper extremity which usually ap- 

 pears nari'ow, like a slit, and this is surround- 

 ed by a dark, well-defined, slightly raised ring. 

 The antenn?e are placed near the posterior ex- 

 tremity of the sac, and resemble closely in 

 form those of S. vulgare. The whole of the 

 sac, with the exception of a small bald patch 

 near the point of attachment, is covered with 

 fine chitinous hairs arranged in transverse 

 rings. There is not the slightest rudiment of 

 a valve, and I could detect no trace of a jointed 

 ""rlgium. thorax, although several specimens were ren- 

 Tweiity times the (j^red vcrv transparent by boiling in caustic 



natural size. (NoC3.) ^ r jo 



potash. There seems to be no oesophagus nor 

 stomach, and the whole of the posterior two-thirds of the body 

 in the mature sj^ecimens was filled with a lobulated mass of 

 sperm-cells. Under the border of the mantle of one female 

 there were the dead and withered remains of five males, and 

 in most cases one or two of the males were not fully devel- 

 oped ; several appeared to be mature, and one or two were dead 

 — empty, dark-colored chitine sacs. 



The concretionary masses to which the barnacles adhered 

 were irregular in form and size. One, for example, to which a 

 large Scalpelhnn was attached, was irregularly oval in shape, 

 about three centimetres in length and two in width. The sur- 

 face was mammillated and finely granulated, and of a dark- 

 brown color, almost black. A fracture showed a semi-crystal- 

 line structure ; the same dark-brown material arranged in an 

 obscurely radiating manner from the centre, and mixed with 

 a small quantity of grayish-white clayey matter. This nodule 



