HALF-AN-HOUK AT THE MICROSCOPE. 181 



their appetites are by no means small in proportion to their size. 

 Indeed, as is often the case with peculiarly meagre human beings, 

 they are most voracious, preying incessantly on every small 

 creature that comes in their way. They are furnished with terrible 

 instruments of prehension, their first and second pairs of legs 

 being devoted wholly to this purpose. The last joint but one is 

 enormously large, and the last joint is thin, and shuts down like 

 the blade of a clasp-knife into its haft, the groove being repre- 

 sented by a double row of spines, between which the blade is 

 received. The blade itself is finely notched along the edge. 

 These claw-like terminations to the legs are used, not only for 

 seizing prey, but for grasping the branches and drawing the long, 

 attenuated body from one part to another." 



Mr. Goss, who has paid much attention to these curious 

 beings, remarks that their movements among the marine vegeta- 

 tion are wonderfully like those of the spider-monkeys among the 

 branches, their long, thin bodies adding to the resemblance. 

 They run about with great agility, and are always to be found 

 among the branches of the Plumatella cristata* The same 

 writer has given a very interesting history of the Mantis-Shrimp : — 

 " Their manners are excessively amusing. The middle part of 

 their body is destitute of limbs, having, instead of legs, two pairs 

 of oval, clear vesicles ; but the hinder extremity is furnished with 

 three pairs of legs armed with spines, and a terminal hooked 

 blade like that already described. With these hindermost legs the 

 animal takes a firm grasp of the twigs of the polypidom, and 

 rears up into the free water its gaunt skeleton of a body, stretch- 

 ing wide its scythe-like arms, with which it keeps up a see-saw 

 motion, swaying its whole body to and fro. Ever and anon the 

 blade is shut forcibly upon the grooved haft, and woe be to the 

 unfortunate infusorium, or mite, or rotifer, that comes within that 

 grasp. The whole action, the posture, figure of the animal, and 

 the structure of the limbs, are so closely like those of the tropical 

 genus. Mantis^ among insects, which I have watched thus taking 

 its prey in the Southern United States and the West Indies, that I 

 have no doubt passing animals are caught by the crustacean also 

 in this way, though I have not seen any actually secured. 



" The antennae, too — at least, the inferior pair — are certainly, 

 I should think, accessory weapons of the animal's predatory 

 warfare. They consist of four or five stout joints, each of which 

 is armed on its inferior edge with two rows of long, stiff, curved 

 spines, set as regularly as the teeth of a comb, the rows divaricat- 



* Note by Tiiffen West : — " If there be no error in this description, it 

 must apply to a fresh-water species, as Plumatella cristata is a synonym of 

 Alcyonella stagttorum." 



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