THE SEA-MOUSE. 533 



curious appendages arise from the alternate segments of the body, and are continued in two 

 rows along the back almost to the very end of the body. 



If placed under a good microscope, the transparent walls of these cirri permit the blood to 

 be seen coursing through them. This is not, however, a very easy operation, as the creature 

 is very timid, and when touched will contract the cirri into a shapeless bundle. When, how- 

 ever, the Cirrhatulus is quite at its ease, recumbent in its rocky home, it permits the cirri to 

 lie flat on the ground, where they surround it like a mass of red worms continually writhing 

 and twining throughout their length. 



It is one of the light-hating creatures, always seeking a retreat under some stone or in a 

 cleft of a marine rock ; and it is, moreover, protected by a mass of sand, mud, and slime, which 

 it collects around its body, so as effectually to disguise its shape. The length of the Cirrhatu- 

 lus is about four inches, and its color is mostly red, with a tinge of brown. 



The members of the genus SYLLIS may "be easily distinguished by the shape of the 

 tentacles, which are jointed in such a manner as to resemble closely the beads of a necklace. 

 The number of the tentacles is always uneven, and this fact serves to separate them from an 

 allied genus, where their number is even. 



The SEA-MOUSE, a creature with a hairy coat, possesses beauties which never fail to strike 

 even the unobservant eye of a casual passenger, as the wondrous hues of ruby, emerald, sap- 

 phire, and every imaginable gem, flash from the coat of this breathing rainbow. Each hair 

 of the Sea-mouse is a living prism, and when held singly before the eyes is a most magnificent 

 object in spite of its small dimensions, flinging out gleams of changing colors as it is moved in 

 the fingers, or the direction of the light is changed. I have often thought that if Shakespeare 

 had only known of the Aphrodite, he might have furnished Queen Mab with a still more fairy- 

 like conveyance. 



Yet the habits of the creature seem to be quite out of accordance with its exceeding 

 beauty. When the sunlight falls on its surface, the many-hued hairs give forth a chromatic 

 radiance which is almost painful to the eyes from its very intensity ; and it would be but 

 natural to conclude that the Aphrodite made its home in the sunniest spots, and welcomed the 

 dawn with gladness. Such, however, is not the case ; for this beautiful creature, which wears 

 all the colors of the humming-bird and seems equally a child of the sun, passes its life under 

 stones, shells, and similar localities at the muddy bottom of the sea. 



The whole group of the Aphroditacea is separated from the rest of the order by reason of 

 the curious mode in which its respiration is conducted. If the beautiful hairs be push'ed aside, 

 a series of scales will be seen upon the back, which are guarded by a covering of a loose felt- 

 like substance, composed of interwoven hairs. This felt, if it may be so called, acts as a filter, 

 which is very necessary, considering the muddy localities in which the creature lives, and per- 

 mits the water to pass in a purified state to the breathing apparatus, which is set beneath the 

 scales. These scales or plates move up and down, something like the gills of a fish, and by 

 their alternating movements have the power of admitting the water and then expelling it in 

 regular pulsations. If a recent specimen be examined, a considerable quantity of mud is 

 always to be found entangled in the felt-like covering of the scales. 



Sometimes this beautiful annelid attains a considerable size, reacliing the length of five or 

 even six inches. Generally, however, from three to four inches is the measurement. It is a 

 slow-going, but very voracious creature, feeding even upon its own kind, and using its power- 

 ful proboscis as a means of capture. 



In some species of this genus, the spines which edge the body are most marvellously 

 formed. They are set upon projecting footstalks, and when not required for use can be 

 drawn back into the body. Their shape, however, would seem to render such a proceeding 

 dangerous, inasmuch as they are formed just like the many-barbed spears used by certain 

 savage tribes. In the ApJirodite Mspida, for example, they are just like doubly-barbed 

 harpoons, and would wound the soft tissues of the body most severely when withdrawn. In 

 order, therefore, to prevent this result, each spine is furnished with a sheath composed of two 

 blades, which close upon the barbs when the weapon is withdrawn, and open again to allow 

 its exit when it is protruded. 



