Zoology.'] NATURAL HISTORY OF VICTORIA. [Polyzoa. 



Plate 108, Fro. 2. 



CHLIDONIA D.EDALA (Wtv. Thomson). 



[Genus CHLIDONIA (Savignt). (Sub-kingd. Mollusca. Class Polyzoa. Order 

 [nfundibulata. Sub-order Cheilostomata. Fam. Chlidoniidae.) 



Gen. Char. — Polyzoary plrytokl, erect, rising from a creeping stolon ; cells in single series, 

 rising from the joints of an articulated, non-celliferous stem, all opening the same way.] 



Description. — The stem of each colony rises by a corneous tube from a disk 

 on the dilatation of a creeping-, anastomising stolon. It consists of a series of long, 

 calcareous cylinders connected by corneous tubes. The upper internode divides 

 into two, each division originating a branch extending in a curved direction out- 

 wards, upwards, and forwards. These are divided into calcareous internodes con- 

 nected by corneous tubes, as in the primary stem. A certain number (2-7 or 8) of 

 the internodes give origin superiorly to the first cells of an erect series. The lateral 

 branch ends in a simple or divided tendril-like filament, jointed in the same manner. 

 The cells are arranged in erect, linear series, each connected to the upper part of 

 the preceding b} r a short, corneous tube. The number varies from 1 to 5 or G in 

 each series, being greatest in those nearest the bifurcation of the central stem. 

 The ultimate cell of each series usually gives rise at its summit to a tendril-like 

 prolongation of similar structure to the extremities of the lateral branches. The 

 cells are wide above, narrowed below, laterally compressed, and very much bulging 

 posteriorly. The anterior surface is flattened, the greater part occupied by a thinner, 

 depressed area separated by distinct margins. The large mouth, situated at the 

 upper part, is rounded above and straight below. Below the mouth there is usually 

 a small, round foramen. Some of the cells are much larger, but not otherwise 

 different, and are probably ovicelligerous. 



It is a very minute species growing on other polyzoa, chiefly 

 Bicellaria. When extended, the whole has a very beautiful 

 appearance, resembling a two-branched candelabrum. 



It was made the type of a new genus by Wyville Thomson 

 (Dubl. Nat. Hist. Rev. 1858), and described as Cothumicella 

 dcedala. It is, however, exceedingly closely allied to the Mediter- 

 ranean Eucratea cordieri, and will probably prove to be a luxuriant 

 form of that species. As, however, the only specimen I have of 

 the latter is not in a very good state of preservation, I am unable 

 to decide positively. Waters's description (Ann. and Mag. Nat. 

 Hist., Feb. 1879), the only one with which I am acquainted, would 

 precisely apply to our species. 



D'Orbigny (Paleontologie Francaise, and V. Bryozoaires, p. 40) 

 first defines Chlidonia, referring to the name as given bv Savigny 



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