THE NEREIDS. 



703 



horny jaws. In the typical genus the eyes are four, arranged in a sort of square, and 

 the tentacles are four in number. The proboscis is thick, strong, and armed with two 

 jaws. 



The beautiful Nereids may be found plentifully on our coasts, mostly hiding under 

 stones and rocks, or hiding in the sand. They are well worthy of examination under 

 the microscope ; and, perhaps, the best method of making out the structure of these 

 beautiful creatures is by taking a single segment and noticing its construction. On 

 the back are seen certain tufts of different shapes in the various species, but all agree- 

 ing in being composed of numerous blood-vessels ramifying in a most complicated 

 manner. These are the gills, or branchiae, of the Nereis. 



On each side are seen the organs of locomotion, sometimes consisting of a single, 

 but mostly of a double, row of oars. Each oar is formed of a strong muscular foot- 

 stalk, from the extremity of which proceeds a bundle of stiff bristles and a variously 

 formed flap, which is technically called the " cirrus." If the bristles be examined 

 separately, their wonderful forms cannot fail to attract admiration. They no longer 

 appear as the simple hairs which the naked eye would assume them to be, but are 



Phyllodoce Parettl. 

 Nereis Margaritacea. 



transformed, as it were, into a very arsenal of destructive weapons, the barbed spear 

 the scimetar, the sabre, the sword-bayonet, and the cutlass, all being represented ; while 

 there is no lack of more peaceful instruments, such as the grapnel, the sickle, and the 

 fish-hook. 



The Nereids will live for a time in a shallow basin half rilled with sea-water, and are. 

 therefore, valuable to those who really desire to study for themselves the beautiful 

 forms with which they are surrounded, and which, but for the microscope, would 

 ever be hidden from our eyes. The observer should not fail to examine the formidable 

 proboscis with its terrible jaws. While the worm is at rest, this proboscis is retracted 

 like the finger of a glove, and the jaws appear to be situated in the neck, where, indeed, 

 they v/ere once taken for a gizzard. But either by dissection or applying pressure in 

 the right direction, the jaws can be drawn out, and are then found to be destructive 

 weapons at the end of the proboscis. Many years ago, while examining, for the first time, 

 a Nereis which I had found on the sea-shore, I took this structure for a gizzard, and 

 find, on reference to my note-book, that a sketch of these internal jaws is marked with 

 the title, " Gizzard of the above." 



