ANNELIDES. 
390 
to the anterior portion of the body. Nearly all of them inhabit tubes, and we term 
them Tuhicolcd. 
Others have upon the middle portion of their body, or all along their sides, branchiae 
in form of arbuscules, crests, laminae, or tubercles, in which vessels ramify. The 
greater number live in mud, or swim freely in the water ; only a very few inhabiting 
tubes. These we denominate Dorsihranchiata. 
Finally, others have no apparent branchiae, and respire either over the surface of the 
skin, or, as is believed in some cases, by their internal cavities. The greater number 
live freely in water, or in mud ; some, however, in humid earth : and we designate 
these Ahranchiata. I 
The genera of the two first orders have all silky bristles, of a metallic colour, upon 
the sides, either simple or in bundles, and which supply the place of feet ; but in the 
third order, there are some genera devoid of all such support.* 
The particular study which M. Savigny has made of these feet or locomotive organs, 
has led him to distinguish, firstly, the foot or tubercle which bears the bristles, of |[| 
which there is either one only upon each ring, or two, one above the other, which he | 
respectively terms a simple or double oar; secondly, the bristles which compose a ;; 
bundle upon each oar, varying much in consistence, and which either constitute true 1 
spines, or fine and flexible filaments, that are often dentelated, barbed, or irregularly ! 
so, &c. ; and thirdly, the cirrhi, or fleshy filaments, adhering either to the inside or | 
outside of the feet. 
With respect to their organs of sense, the two first orders of Annelides have gene- 
rally tentacles to the head, or filaments, which, notwithstanding their fleshy consis- 
tence, some moderns have designated antennae ; and several genera of the second and 
third orders have black and shining points, which have been regarded as eyes. The 
organization of the mouth varies exceedingly. 
[The Annelides constitute one of the many small, but singular and highly interesting, ^ 
tribes of animals, which, from being upon the confines of the peculiar class or sub- i s 
kingdom to which they in effect belong, exhibit, in a remarkable degree, the modifi- r 
cations of other higher groups : thus, by an ordinary observer, these creatures would 
be at once classed as Worms ; and the common Earth-worm, one of them, would be i 
regarded as the type of the grand class of Linnsean Vermes, the great majority of which, J || 
however, do not even belong to this great subkingdom, but to that of the Zoophytes, ; 
from which these articulated animals are at once distinguished by the possession of red 
blood circulating in a well-defined system, and a far more perfect developement of the ; 
nervous system ; still, in their vermiform appearance, and in the elongated filaments ; 
with which many of them are furnished, they resemble certain Zoophytes, — on the ; 
other hand, they approximate to the most imperfect Fishes, such as the Lampreys and : 
others, in which the spine has disappeared. Their annulose character, and nervous ] 
system, however, bring them nearer to the true Annulosa, especially the Myriapoda ; 
this will at once be evident by comparing the figures of Geophilus longicornis, given in j 
p. 486, with that of Syllis monilaris here figured.f Mr. Mac Leay accordingly con- 
* M. Savig^ny has proposed a division of the Annelides according to 
their possessing locomotive silky bristles, or not so ; reducing the 
latter to the Leeches. M. de Blainville, who has adopted this idea, 
ranges the bristled Annelides as a class, termed Entumozoaires Che- 
topodes, and the others as one designated Entomozoaires Apodes; but 
he mingles with the Apodes many intestinal Worms, which M. '■ 
Savigny does not admit. .n 
t Mr. Mac Leay considers that they form the immediate connexion ' 
between such Vertebrata as Amphioxus and Myxine, and such Aimn- j ‘ i 
losa as Porocephalus, and other white-blooded Vermes, which have il ’( 
the sexes distinct. {Ann. Nat. Hist., Feb. 1840.) j 
