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Show 390 nn- I- B. BOWERBANK O N T H E O N E L L A . [May 27, his researches. Tims in the second line of his generic description he says:-" Internally formed of netted spicules arranged so as to leave an hexangular mass; the spicules subcylindrical, united at the inosculation of the network by a siliceous callosity." This is certainly the most incomprehensible description of a purely siliceo-fibrous network that can possibly be imagined; and the figure he has given of the reticulations of a portion of the skeleton-structure, P. Z. S. 1868, fig. 2, p. 566, at once contradicts his description. Throughout the remainder of his description he continues to describe the siliceo-fibrous structure as spicula. In the first paragraph, p. 565, the author writes:-"The sponge in some external characters is like the genus Macandrewia (Dactylo-cali/ x, Stutchbury), but it differs from that sponge in not having any stellate spicula." It is quite true that the Formosan sponge has no "stellate spicula;" but neither has the Doctor's Macandrewia azorica; so that it is not " the only sponge of the family in which they are not discovered." The author describes the long slender interstitial spicula intermixed with the fibrous skeleton; but it is a singular circumstance that he appears to have entirely failed in detecting the remarkable forms of connecting spicula on the dermis, which I have designated as irregularly furcated patento-ternate, and which were first figured in the Phil. Trans. R. S. 1858, plate xxix. fig. 8, in situ, and fig. 9 as separated bv nitric acid ; and they are also represented in P. Z. S. 1869, Plate V. fig. 9, in situ, and figs. 9, 10 & 11 in the separate condition ; and it is stated in the first part of my paper on the siliceo-fibrous sponges that they belong to m y Dactylocalyx Prattii. These spicula certainly form the most prominent specific characters of the sponge, and they are so abundant in the expansile dermal system of the animal that it appears singular that any approach to a careful examination of its structure should fail to immediately discover them ; nor has the author observed the minute entirely spined fusiformi-cylindrical spicula which are so abundantly dispersed on the surfaces of the dermal and other membranes of this species of sponge, and which are represented in Plate V. fig. 7, P. Z. S. 1869. Thus the author has been led into the error of believing the sponge to be the type of a new genus by merely abstaining from a careful and proper examination of the structural peculiarities of the specimen under consideration. I will not reiterate the description of the Formosan specimen that I have given in my paper, P. Z. S. 1869, in m y history of Dactylocalyx Prattii; I will quote only a few lines comparing the two specimens under consideration:-" The sponge is fortunately in very nearly as fine a state of preservation as when taken from the sea ; and every organ that is found in the type specimen appears in abundance in the one from Formosa. In truth, portions of the structures taken from the one specimen cannot, by microscopical examination, be distinguished from those mounted from the other." |