Aug. 10, liti3.] 



KNOWLEDGE ♦ 



89 



skeletons. Such varieties are used in America for stuffing 

 cushions, bedding, and other upholstery work. 



Yet other keratose sponges possess, in addition to their 

 fibrous network, a number of siliceous spicules, which 

 strengthen their skeletons, and also lie embedded in their 

 fleshy substance {e.g. SpowjUIa, llalichoiidria) ; they are, 

 therefore, of no special commercial value, although, as 

 we shall show later on, they are of vast interest to the 

 naturalist. 



When the siliceous spicules predominate, and, finally, 

 when they entirely take the place of the keratose, the 

 sponges are known as siliceous ; and amongst these are 

 some of the most beautiful forms in nature. Fig. 10 is 

 but a poor representation of the delicate beauty of one of 

 these forms which occurs around the region of the Philip- 

 pine Islands, and several specimens of which may be viewed 

 in the Exhibition; more notably in Lady Brassey's .Sw;;,- 

 heam collection, and in two beautiful groups encased in 

 dome-shaped glasses at the end of the Natural History 

 Galleries. We shall have occasion hereafter to give a 

 brief description of the structure of these and other 

 sponges. 



We are indebted for these figures to the kindness of 

 Messrs. Griflith A- Farran, of St. Paul's Churchyard, from 

 whose work, " The Commercial Products of the Sea," by 

 P. L. Simmonds, they have been derived. 



T 



SEA ANEMONES 



AT THE FISHEKIES EXHIBITION. 



By Thomas Kimbee. 



II.— THE WHITE CARNATION. 



AcUnoldba iianiJius (Blainville). Actinia penta'petala {Verm). 



HIS is one of the largest of the British sea anemones. 



and also one of the handsomest. Large specimens- 

 over a dozen of the purest white — may be seen in Ko. 10 



livo princiiuil lubua siiliili 



tank, and still larger — -t or 5 inches across and 6 in height 

 — in some of the other tanks ; while there are j-oung 

 midgets not larger than a pea, with all intermediate sizes. 

 Fig. 1. The disk, ttc. — In this species the piincipal lobes 



or petals vary in number from five to eight or nine, and 

 each lobo is frequently subdivided and voluted, so that the 

 entire disk, though truly circular in outline, will not 

 expand into a plane surface. The tentacles are numerous 

 in the adult near the mouth, and moderately long, but 

 shorter near the margin ; and the edges of each lobe and 

 its sub-divisions are fringed with fine short tentacles that 

 defy numeration. When the disk is much convoluted, as 

 is usual in large specimens, it assumes a semi-globose form, 

 and has a feathery surface. Hence the expressive name 

 plumosa, given to this anemone by several writers. The 

 mouth has a thick lip, divided into lobes, and is generally 

 rufous or orange, whatever the general colour of the 

 animal may be. 



Fig. 2. — Column, edge of disk, kc. 



Fig. 2. The column, &c. — A full-grown specimen in 

 fiower, as here shown, is a very beautiful object, and the 

 greatest possible attraction to any aquarium. At the 

 summit of the column is a thick, round rim, like a ring, 

 and behind it the fosse. The base is always very much 

 Itroader than the rest of the body. Tlie white variety, 

 which Figs. 1 and 2 illustrate, is not at all uncommon, and 

 to it is universally conceded supremacy in beauty. Gene- 

 rally speaking, whatever the hue, it is uniform throughout 

 in the same specimen. The commonest varieties are pro- 

 bably buff and cream colour, and then pale red. Amber, 

 dark brown, and olive are comparatively rare varieties. The 

 brown and olive examples have whitish tentacles, marked 

 with an opacjue bar. Several good examples of the olive 

 dianthus with smoky-white disk, occur in the Exhibition. 



The Button. — This anemone is e.xceptionally flat when 

 closed, and to-day (July 31), in Id tank, are good instances 

 of the button form, both white and buff, and in difi'erent 

 sizes. The outline of a large one is quite irregular, perhaps 

 five inches across, thin as a card at the edges, and in the 

 centre not more than the eighth of an incli in thickness. 



