356 Mr. E. A. Minchin on the 



from con'acea and its allies, we find ourselves confronted with 

 three generic groups amongst the Ascons. The question at 

 once arises, What are these three genera to be called ? To 

 decide the problem of their proper nomenclature we must 

 shortly review the systematic history of the Ascons, noting 

 the generic names that have been proposed in chronological 

 order. 



In 1786 Ellis and Solander * described the first-known 

 A scon under the name of Spongia lotryoides. 



In 1812 Montagu f described two more species — Spongia 

 complicata and S. con'acea. 



In 1828 Fleming J instituted the genus Orantia for calca- 

 reous sponges, the first species being G. compr-essa, Fabr., 

 the second G. hotryoides^ under which he wrongly placed 

 complicata as a synonym. 



(At slightly later dates the names Leiicalia and Calci- 

 spongia were proposed by Grant and de Blainville respectively 

 in the same sense as Grantia, but never obtained a place in 

 the literature.) 



In 1862 Schmidt § described two new species [Grantia 

 Lieherhiihnii and G. pulchra) and instituted a new genus 

 (Nardoa) for a third new species [Nardoa reticulum) . But 

 the name A'ardoa had been used by Gray in 1840 for a genus 

 of Asteroidea, and cannot therefore be employed for calcareous 

 sponges. 



In 1864 Bowerbank || founded a new genus for Ascons — 

 Leucosolenia — with L. botryoides, Ellis, as type species, Grantia 

 being used for Sycons, with type G. compressa, Fabr. 



In the same year 0. Schmidt ^ described " Grantia 

 clathrus,^^ sp. n. 



In 1866 Bowerbank** enumerated four species of his genus 

 Leucosolenia — L. hotryoides, L. contorta, sp. n., L. lacunosa^ 

 and Zy. coriacea. 



In the same year Schmidt ft published a criticism of Bower- 



* ' The Natural History of many curious and uncommon Zoophytes ' 

 (London), p. 190, tab. Iviii. tigs. 1-4, 



t "An Essay on Sponges &c.," Mem. Wernerian Nat. Hist. Soc. vol ii. 

 pp. 89 et seq., pi. ix. figs. 2. 3. 



X ' A History of British Animals ' (Edinburgh, 1828), p. 525. 



§ ' Die Spongien des adriatischen Meeres ' (Leipzig, 1862), pp. 13-19, 

 Taf. i. figs. 8-8 b. 



II 'A Monograph of the British Spongiadae,' vol. i. (Ray Society), 

 p. 164, figs. 347, 348. 



^ ' Spongien des adriatischen Meeres,' I. Supplement (Leipzig, 1864), 

 p. 24, Taf. iii. tigs. 3, 3 a. 



** Op. cit. vol. ii. pp. 28-36. 



tt Op. cit. II. Supplement, pp. 7, 8. 



