LINNEAN SOCIETY OF LONDOIf. 71 



1830, bears tlie announcement (dated by Thompson December, 

 iy20) that tlie Fourth ]Vumber will contain " a Memoir on PoJi/zoa, 

 a new animal discovered as an inhabitant of some Zoupliites." 

 The speaker considered that Thompson's clear realisation of the 

 effect his discovery must have in altering current views with 

 regard to the classification of Zoophytes constitutes ample 

 justiiicatiou for preferring " Polyzoa " to " Bryozoa." 



(0 



Me. a. W. Waters said that his reasons for using the term 

 Bryozoa were given many years ago, and he had recently restated 

 his hrm adherence to the view arrived at. But it will be well to 

 first clear up a mistaii.e which has misled many, for most naturalists 

 have looked to Busk's ' Crag Polyzoa ' to see why he changed 

 from Bryozoa to Polyzoa ; and speaking of Thompson, Busk 

 writes : " The term he employed was Polyzoa, ' it being applied,' as 

 he says, ' to a distinct class of Polypes hitherto in great measure 

 confounded with the Hydroida ' " : although this is given as a 

 quotation, in inverted commas, Thompson never said anything of 

 the kind, and a critical examination shows how impossible it 

 would have been for him to have wi-itteu it. 



The speaker said his point had always been that Thompson gave 

 no indication that he was establishing a class. The paper is on 

 " Polyzoa, a new animal discovered as an inhahitant of some 

 Zoophiles,'^ and then he speaks of the animal as Polyzoa, and this 

 idea of the animal being a Polyzoa, but the animals Polyzoje, is 

 repeated several times in the paper. Thompson considered that 

 a certain section of the zoophytes must ultimately be separated, 

 as the polypides were not hydra, and we must remember that at 

 that time the polypes of Hydrozoa were still ppoken of as flores, 

 and there were perhaps naturalists still living who had believed 

 that the poly])ides of Flicstra could leave the zocecium whenever 

 they wished, just as a bee can leave its cell. 



A year before Thompson's paper, Cuvier had separated the 

 Bryozoa as " Polypes a cellules " as a distinct family from 

 " Polypes vagiuiformes," namely the Hydrozoa, but said the 

 animals in both cases resemble Hydrse. 



It has been urged that Thompson having seen the great 

 difference between the Bryozoa and other zoophytes, we ought to 

 honour him by retaining the name Polyzoa. However, if he did 

 not create the class we must remember that he was not the first to 

 publish the difference, for Dr. Grant (1827) had seen that a 

 separation must be made, and he based it upon the Bryozoa having 

 no common cocnosarc, but, though he described the polypide 

 correctly, he did not recognise that the digestive tract had two 

 openings. Then Audouin and Milne-Edwards (1828), studying 

 the marine invertebrates of Chausey, divided the Polypes, or 

 Zoophytes, into four families, and these were, as we should say, 



