64 PnOCKEDINGS OF TUB 



On Jonx VxconAN TnoMrsox and liis Polyioa, and on Vaun- 

 thonipsonia, a genus of Sympoda. By the Rev. T. li. li. 

 iSiJiuuiNG, M.A., IMl.S., F.L.S. 



John Vaughan TuowrsoN was born in 1779 and died in 1847. 

 The Ijiniean Society with prophetic instinct elected him a Fellow 

 on Fehniary Cth, 1810. It would be an honourable thinj^ to 

 romniemorate that centenary by a re-issue of his writing*, which 

 are small in compass, dilliiMilt to obtain, but of great historic 

 interest and value. In 1830 he made a pathetic appeal to the 

 scientific world to furnish liim with a hundred and iifty .subscribers, 

 as (lis private income would no longer bear the sacrifice till then 

 entailed by the publication of his reseiirches. lie had good reason 

 to be proud of his " discoveries," though he may not have been 

 the first to make them. That is the lot of all discoverers, as 

 CoUimbus, for example, in finding the New World found it already 

 peopled by men who had known it before he was born. None the 

 less, Vaughan Thompson was a foremost leader in proving that 

 cirripedes ( Thyrostraca) are crustaceans and that crustaceans as a 

 rule pass through metamorphic stages, lie was also undeniably 

 in the vanguard of those who proved that the term Zoophytes had 

 been used to cover a mixture of animals superficially alike but 

 essentially different in structure. 



In regard to this latter part of his investigations, a curious 

 terminological dispute or difference of usage has arisen. While 

 practically all Contiiiental and American writers speak of a class 

 Bryozoa, a very distinguished section of British experts apply 

 the name Polyzoa to a class identically the same. Possibly the 

 arguments in favour of either term may be so evenly balanced that 

 after discussion we shall leave off where we began, each side 

 thinking that it has had the better in the controversy and applying 

 to those of the opposite opinion the French proverb " Chacuii a 

 son gont,"or,as sometimes amplified, "Chaeun a son vilain gout."' 



On the one hand, then, it may be urged that no confusion can 

 arise from the retention uf both the terms. They have become 

 perfectly familiar as equivalents. Some writers even head their 

 treatises " Bryozoa or Polyzoa," as though it were a matter of 

 complete indifference, and perhaps wishing to insinuate to the 

 disputants " a plague on both your houses." Further, it is clear 

 that the names of classes and orders have never been subject to 

 80 strict a discipline as the names of genera and species, probably 

 because, while the limits of the higher divisions remained 

 essentially unstable, fixity in their designation has been felt to be 

 inconvenient or unreasonable. In fact, as Lord WaUingham has 

 urged in the introduction to his Merton Code, the moral law, the 

 law of giving every man his due, is the strongest foundation on 

 which any precise methods can be based. 



Again, it may be argued that any defect in the form of 



