82 PARASITES ON SEA-WEED. 



the base a frond of the Digitate Oar- weed, the footstalk 

 of which was densely crowded with a parasitical forest 

 of the angular stems of Laomedea geniculata as thick 

 as they could bristle. A considerable number of 

 stems of that lovely feather-like zoophyte, the Crested 

 Plumularia, were also springing from the root of the 

 Oar-weed, most of which were studded with curiously 

 folded ovarian vesicles in various degrees of maturity, 

 A small Mantis-shrimp, (Caprella) of curious form 

 and the most delicate transparency, which I have 

 found to make its favourite home upon this zoophyte, 

 was upon the plumes in some numbers, and a few 

 were also upon the Laomedea. Its habit is to take a 

 firm hold of the zoophyte with its hindermost feet, and 

 to rear its long spectre-like form in the free water, 

 through which it sways backward and forward, catching 

 with its singularly constructed fore feet for any strag- 

 gling prey that may be passing, exactly in the manner 

 of that curious predaceous insect, which in habit, as 

 well as in structure, it so closely resembles. 



Many of the stems of the Laomedea were studded 

 with little oval masses of white spawn, each enclosed 

 in a ball of transparent jelly, the largest not so big as 

 a small pin's head. These were doubtless the spawn- 

 masses of the minute Eolides of the section Tergipes, 

 so readily distinguished by having the branchise dis- 

 posed in large but few club-shaped excrescences, 

 growing along each side of the back. 



I put the whole stock into a glass of water; and the 

 next morning on searching over it with a lens I dis- 

 covered adhering to the side of the vase a specimen 

 of the pretty Eolis despecta, which I had no sooner 



