96 REPORT — 1867. 



Oil the Nature and Systematic Position of the Grajjtolitidce. 

 By Henry Alleyne Nicholson, D.Sc., M.B., F.O.S. 



The author of this paper, after reviewing- the various theories wliicli have been 

 held as to the nature and affinities of the Uraptolitidte, endeavoured to show that 

 they should be referred to the Hydrozoa — a view which he believed was supported 

 by their morphology, development, and reproduction, by their mode of existence, 

 and by the determination of allied forms. The " common canal " of the Graptolite 

 was shown to be strictly analogous to the " coeuosarc " of the Hydrozoa, no similar 

 structure existing in any Bryozoon, whilst the " cellules " found their nearest re- 

 presentative in the " hydrotheca; " of the Sertularians. It was further pointed 

 out that there existed, in several species of the genera Dichor/rapsus, Tetra- 

 ffrapsus, and Diployrapsug, an organ whicli had been compared with the basal 

 plate of Dcfrcincia, a JBiyozoon, by Prof. Huxley, but which was more probably 

 homologous with the " tioat " or " pneumatophore " of the Physophoridae, an 

 order of the oceanic Hydrozoa. 



As regards their reproduction the author drew attention to the bodies first de- 

 scribed by Hall in America and by himself iu Britain, and considered to be the 

 " ovarian capsules " of Graptolites. He pointed out, further, tlie resemblance of 

 these to the "gonophores" of the recent Hydrozoa, both in their shape, and as 

 regarded the changes through which they were observed to pass. 



With regard to the mode of existence of the Graptolitidai, it was shown that by 

 far the majority must have been free and permanently imattached — a fact highly 

 adverse to the belief that they belonged to the Polyzoa. 



Lastly, the author noticed the occurrence of a form, originally described by him- 

 self under tlie name of Corynoides calicularis, closely allied to the true Graptolites, 

 but apparently representing the order CorynidiB (or Tubularidre). 



In conclusion, the author stated it as his belief that the Graptolitidaj could not be 

 referred to any existing order, or eyen subclass, of the Hydrozoa, but that they 

 stood in the same relation to existing forms that the Trilobites hold to the recent 

 Crustacea. In their mode of growth, in the arrangement of their parts, and in the 

 natiu-e of their structural elements they were seen to resemble the Ilydroid polypes ; 

 but they were widely separated by their free " hydrosoma." On the other hand, 

 the}' approximated to tiie oceanic Hydrozoa in the fact that they were free- 

 Hoating organisms, and in the possession, by some forms, of an organ resembling a 

 "float." On the whole the author was of opinion that the Graptolitidie should be 

 held to constitute a new subclass intermediate in position between the fixed and 

 the oceanic Hydrozoa, and that the}' might possibly, on the derivative theory of 

 development, be looked upon as the primitive stock from which the above existing 

 sections of our li\iug Hydrozoa had originally diverged. 



On the Fructification of Griffithsia corallina, found in the West Voe, Ouf- 

 skerries, Shetland. By C. W. Peach. 



In May 1864, when in Shetland with Mr. J. G. Jeffreys on a dredging excur- 

 sion, Miss Jeffreys found some fine specimens of Griffithsia corallina, wliich, on 

 examination, the author found in fruit and in fine condition. I'nder the micro- 

 scope he observed a circular opening in the lower part of the joint above the fruit 

 (tetraspores), from which opening the granular pulp of the joint was poured on 

 the fruit under it. Harvey, iu his introduction to his 'British Marine Algie,' gives 

 a long account of the fructification ; but there is nothing in it that fully agrees with 

 the above. 



On NaTced-eyed Medusce found at Peterhead and Wich, N.B., and other Bri- 

 tish Localities. By C. W. Peach. 



The author first stated that during his residence in Edinburgh he had oppoiiuni- 

 ties of examiniug books not before accessible to him; by these he found that many 

 of the naked-eyed medusEC that he had found were new to the British list. He then 

 described one he got in Cornwall in 1849, which he thought was Willsia stcl- 

 lala of Forbes, but after carefvd examination, and comparing it with others, is 

 satisfied that it is a new species, and has named it Willsia Cornuhica ; it has only 



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