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Show 352 PROF. E. A. MINCHIN ON THE BRITISH [Dec. 13, (! rant's genus Leuconia for nivea, and placed botryoides in a new genus Leucosolenia. In making these changes Bowerbank acted with perfect correctness, according to accepted modern rules of nomenclature; and it is clear that for the species botryoides the generic name Leucosolenia has the priority over all other generic names for it, or for other species associated with it generically. Leucolosenia is, in short, the first generic name put forward which has an undoubted Ascon as the type species. Bowerbank added various species to his genus Leucosolenia, amongst them forms which, in my opinion, cannot be associated generically with botryoides, and therefore do not belong to the genus Leucosolenia as here understood, but to that section of the Ascons for which I employ the generic name Clathrina (Gray, 1867). Moreover, Bowerbank did not properly understand the distinctions between the different species which he dealt with, so that different species are found confused together in his monograph in an extraordinary manner, and his descriptions are sometimes quite incorrect. Thus the specimen described and figured as L. botryoides in vol. i. of his monograph (p. 164, figs. 347, 348, pi. xxvi.) does happen to be a genuine specimen of botryoides. This can be seen at once from his figure 348, which is extremely characteristic, and I have been able to examine this specimen and have figured its spicules (text-fig. 98, figs. 27 a-g, p. 390). On the other hand, the specimen figured as L. botryoides, in vol. iii. pi. iii. fig. 1, is a specimen of the species described by Haeckel under the specific name variabilis, and the description given by Bowerbank of the triradiate spicules as " equiangular " (vol. ii. p. 28, vol. iii. p. 7) can be seen, even from his figures, to be incorrect. Bowerbank further described a new species under the name " Leucosolenia contorta." I hope to discuss the rather complicated question of the characters and synonymy of this species in another memoir, the true contorta being a Clathrina. I will only say here that amongst specimens identified by Bowerbank as contorta I have found a Clathrina species mixed up with specimens of Leucosolenia complicata and variabilis. Bowerbank himself considered (vol. ii. pp. 30, 31) that his species contorta might be synonymous with Montagu's species complicata, but was more inclined to regard Montagu's figure of the latter as being " a very characteristic figure of Spongia botryoides Ellis & Solander," and thought it better under the circumstances to reject the term complicata altogether. Finally, in vol. iii. of his monograph, Bowerbank described and figured a sponge found in Brighton Aquarium under the name of Leuconia somesii (pp. 334- 332, pi. xci. figs. 6-17). A glance at his figures makes it obvious that this sponge is a Leucosolenia, but his description is inadequate for determination of the species. Having been able to examine Bowerbank's types of this species in the British Museum, I found them to be merely aberrant specimens of Leucosolenia variabilis (Haeckel), as Topsent had already suspected, characterised by the great development in the number and length of |
