CKPHALolHsrrs 



CKI'IIISSUB 



69 



in Uritiiin, part i. ' Cephalaspidiu ' (Lond. 

 186&-70); R. H. Traquair, The Ganoids of the 

 Ji Carboniferous System (Palieont. Society, 

 I,..M.|. IS77). 



(Vplialndisrus. one of tlio most curious ami 

 interesting organisms dredged ly the Challenger 

 expedition. It was found in the Strait of Magellan, 

 \v.-i- lir>t -uppnsed to be a compound Ascidian, was 

 monographed (1887) by Prof es.sor M'Intosh as one 

 of ill-- 1'oly/oa (section Aspidophora), but is re- 

 garded liv Sir Marnier as closely allie<l to that mar- 

 vellous vertebrate-like worm, Balanoglossus (q.y.). 

 The organisms form a spreading seaweed-like 

 brownisn colony, measuring in some cases 9 inches 

 , and including a groat number of little indi- 

 viduals, protected by a membranous, flexible invest- 

 ment or house. Each individual resembles Balano- 

 glossus (and also in part backboned animals) in 

 many important points, such as () the presence of 

 nil-elite; (b) the existence of a notpchord as a 

 dorsal outgrowth from the gut, growing forwards 

 into the anterior region or proboscis; and (c) the 

 possession of a dorsal central nervous system, most 

 richly developed in the middle region (or collar), 

 but extending on to the proboscis. As another 

 apparent connecting link l>etween invertebrates 

 and vertebrates, Cephalodiscus is of the greatest 

 zoological interest. See zoology of the voyage of 



Cephalodiscus. 



H.M.S. Challenger, Part Ixii. ; Report on Cephcdo- 

 ilisi-Hs, by Professor W. C. M'Intosh and Mr S. F. 

 Manner. 



4 Vphalonia (anc. Cephallenia ; Homeric Same), 

 the largest of the seven Ionian Islands (q.v.), lies 

 opposite the entrance of the Gulf of Lepanto or 

 Corinth. It is irregular in shape, with a maxi- 

 mum length of 30 miles, and an area of 302 sq. m. ; 

 pop. 80,178. The surface is mountainous, in one 

 point attaining 5310 feet ; the soil for the most part 

 thin, and water scarce. The inhabitants, however, 

 ha\c planted vineyards wherever the grape will 

 grow, and currants and olive-oil are also produced 

 :r i- x port. The capital is Argostoli (q.v.). 



Ceplialo'poda ( Gr. , head-footed '), the highest 

 class of molluscs, and in some respects the highest 

 invertebrates. They are usually large animals, 

 exclusively marine, with well-developed head- 

 region, but (as the quaint name suggests) with the 

 ' foot ' or ventral surface grown round the mouth, 

 and- split up into 'arms,' which (with one excep- 

 tion) bear suckers. Another part of the foot is 



modified to form a funnel through which water ifl 

 squirted. Two or four gills are present in the usual 



Cuttle-fish (Sepia officinalis), swimming and at rest. 



mantle-cavity. While the ancient forms lived in 

 shells, the Nearly Nautilus alone remains in this 

 state, the shell being in all other cases internal and 

 degenerate. The eyes are peculiarly large, and 

 their ferocious aspect has earned for many common 

 forms the title or 'devil-fish.' The mouth in the 

 midst of the 'arms' is equipped with parrot-like 

 teeth, and with a rasping ribbon on the tongue. The 

 central nervous system, with its closely associated 

 ganglia, is surrounded by a protective cartilagin- 

 ous sheath, analogous, though in no way homolo- 

 gous, with a verteorate brain-box. The sexes are 

 separate. The structure and life of these animals 

 is discussed under the more familiar title CUTTLE- 

 FISH ; only the general characters, classification, 

 and distribution are here noticed. 



Classification. The Cephalopoda include two 

 distinct orders, one represented by the Pearly 

 Nautilus, the other by all the other living forms, 

 which are again divided into Octopoda and Deca- 

 poda, according to the number of the 'arms.' 



DlBRANCHIATA. 



Two gills, kidneys, auricles. 

 Eight or ten sucker-bearing 



arms. 

 Shell rudimentary or absent, 



never external, in one case 



chambered. 

 An ink-bag. 

 A completely closed funnel. 



TETRABRANCHIATA. 

 Four gills, kidneys, auricles. 

 Numerous, without suckers. 



Shell well developed, external, 

 chambered. 



No ink-bag. 

 A split funnel. 



Distribution. Most species occur in warm and 

 temperate seas, but those found in the colder waters 

 seem much more prolific. The Tetrabranchiata are 

 the older forms, and begin in the Silurian, whereas 

 the Dibranchiata first appear in Triassic times. 

 The Ammonites (q.v.) are the most familiar re- 

 presentatives of the former, the Belemnites (q.v.) 

 of the latter. 



See especially CUTTLEFISH, NAUTILUS, BKLKMNITES, 

 AMMONITES ; also CALAMARY, OCTOPUS, SEPIA ; Owen, 

 Memoir of the Pearly Nautilus (1832); Fdrusaac 

 and D'Orbigny, Histoirc naturelle det Cephalopoda (2 

 vols. Paris, 1835-48); Hoyle, Challenger Report on 

 Cephalopoda. 



Cephaloptera, a name formerly used for a 

 genus of rays. See RAY. 



CepllissilS, one of the two rivers which water 

 the Athenian plain. It rises on the western slope 

 of Mount Pentelicus and the southern side of 

 Mount Parnes, and flows past Athens on the west 

 into the Saronic Gulf near Phalenuu. 



