96 CLIIDA. 
OrpvEeR GY MNOSOMATA. 
Animal naked, without mantle or shell; head distinct; fins 
attached to the sides of the neck, without intermediate lobe ; 
gills indistinct (Clio), or distinct (Pneumodermon); teeth 
numerous. 
The embryos are at first Thecosomous, having a straight shell, 
ovoid at the extremity ; they swim by means of a ciliated velum; 
subsequently, they lose the shell, and the body is encircled by 
rings of ciliz (xx, 53, 55), which in turn disappear as the animal 
assunies its perfect form. 
Faminty CLIID 2. 
Body fusiform ; head with tentacles often supporting suckers ; 
foot small, but distinct, consisting of a central and posterior 
lobe. 
Cuio (L.), Muller, 1776. 
Etym.—Clio, a sea-nymph. Syn.—Clione, Pallas, 1774. 
Distr.—10 sp. Arctic and Antarctic Seas, Norway, Mediter- 
ranean, India. 
Head with two eye-tubercles and two simple tentacula; mouth 
with lateral lobes,each supporting two or three conical retractile 
processes, furnished with numerous microscopic suckers; fins 
ovate; foot lobed. Dentition 12°1:12. In swimming, the Clio 
brings the ends of its fins almost in contact, first above and 
then below : Scoresby). 
C. borealis (xlii. 2,5) is largely the food of whales; the Clio 
and other pelagic animals are attracted to the large bodies of 
Diatomacex which discolor the Arctic seas, and on which they 
feed. The whale in turn lives upon them, and whalers hail the 
appearance of these discolored patches of ocean-surface as indic- 
ative of a good oil-harvest. 
CLIODITA, Quoy and Gaimard. Head supported on a narrow 
neck ; tentacles indistinct. 4sp. Cape, Amboyna. C. fusiformis. 
Cuionopsis. Troschel. 
Distr.—C. Krohnii, Trosch. (xlii, 26). Mediterranean Sea. 
Body ovate, head keeled, mouth armed with three jaws; two 
lateral tentacles ; fins two, oblong, lateral, anterior, with a trun- 
cate intermediate lobe; a ciliated ring around the hinder part of 
the body. 
The ciliated ring around the base of the head, and similar ring 
around the middle of the body, seen in Trichocyclus (Pneumo- 
dermon), are wanting in this genus. 
PNEUMODERMON, Cuvier, 1804. 
Etym.—Pneumon, lung (or gill), derma, skin. 
