VINE : MICRO-PAL.EONTOLOGY. 



209 



writes (Quart. Jour. Geol. Soc, Nov. 1884, p. 675): 'Among the 

 Palaeozoic fossils there is in one or two a structure which may represent 

 the suboral pore or avicularium,' and as long as we do not know 

 the signification of the ' adventitious tubules ' of Diastopora obelia, &c., 

 we may be justified in asking if they may not possibly have had an 

 homologous origin. The same, or at least a similar thought 

 occurred to the Messrs. Young of Glasgow, the original describers of 

 this species {^D. 7?ia7'ginalis), and also in their description of Acantho- 

 poi'a stellipora, for they say (Quart. Jour. Geol. Soc, Dec. 1874, 



p. 682-3): 'Two interpretations of these openings are possible 



The smaller plainly cannot be regarded as that of the ovicell ; 

 the only other structure to which it can be compared is an avicularian 

 appendage, and if this be correct, some at least of the Palaeozoic 

 Polyzoa would belong to the order Cheilostoinata' It will be well 

 to bear these suggestions in mind, and any light that can be 

 thrown upon the subject must be of value to the special worker. 



Sub-order cbyptostomata Vine. 



Fam. RHABDOMESONTIDy^ Vine (Naturalist, Oct., p. 65-6). 

 Genus RHABDOMESON Young and Young. 



4 Rhahdomeson gracile (Phill. sp.). 



5 Rhabdomeson rhombiferum (Phill. sp.). 



Both of these species are present in the Skelly Gate Shales, but 

 are very much crushed. 



Fam. MONTICULIPORID^ Nicholson. 

 Genus ARCH.EOPORA D'Koninck. 



6 Archseopora nexilis Vine (D'Koninck's sp.). 



There is one small fragment of a colony of this species, adherent 

 to one of the broken spines of Producius spiniilosus Sow., which are 

 very abundant in the Skelly Gate Shales. 



ENTOMOSTEACA. 



Since this paper was written, Mr. J. W. Kirkby has provided me 

 with the following list of species which he wishes me to print as pro- 

 visional only, and I do this with greater pleasure because I wish to 

 draw attention to the Entomostraca of Skelly Gate. I am unable to 

 add to the following list of species, because the original sample sent 

 to me by Mr. Howchin from this locality is exhausted : all the 

 organisms have been picked out by me, and the full results are given 

 in this paper. 



7 Cytherella sp. not yet determined. 



8 Cytherella valida Jones and Kirkby. 



April 1885. 



