PROCEEDINGS OF SOCIETIES. 121 



ciliated, and they are prolonged below into a slender stii)es-like 

 posterior extremity, all these running towards a common point in 

 the centre of the colony-. These filiform stalk-like prolongations 

 seemingly divide with ever\' self-division of the bodies at the peri- 

 phery, being sometimes simply forked, at others divided into four, 

 each upper extremity bearing one of the monad-like structures, thus 

 presenting a certain amount of parallelism with the algal genus 

 Dictyosphaerium. Nay, the resemblance is thus greater to Uvella, 

 or even to the forms brought forward at last meeting, one of which 

 was doubtless the same thing as that called Monas consociata by 

 Fresenius. The organism now shown, believed to be nothing else 

 than Synura uvella, differed, indeed, from Monas consociata by the 

 far less dense character of the mucous matrix, and by the tail-like 

 or stalk-like terminations, and by the far more active motion of the 

 total colony. But, notwithstanding these resemblances, the orga- 

 nism now brought forward was clearly, a priori, quite a distinct 

 thing in itself from either Monas consociata, Uvella, or Yolvox, or 

 Pandorina, or from the so-called Sphcei^osira Volvox ; and it is hard 

 to see how so very distinct structures as the Synura and all these 

 could be evolved the one from the other. It is satisfactory, until 

 further research is bestowed on these organisms, to see that Diesing 

 keeps them separate (' Revision der Prothelminthen,' p. 377), for 

 it does not seem justifiable to consider such forms as Synura as not 

 autonomous merely on suspicion, for whilst volvocinaceous plants 

 without doubt pass through very remarkable phases, Mr. Archer 

 would venture to think that Synura hardly seems truly volvoci- 

 naceous at all. 



Kev. E. O'Meara reported that certain diatomaceous materials 

 submitted to him for examination by the Club had been investigated 

 by him with the following result : 



No. 1, from the Greysers, Iceland, contained several species of 

 Epithemise, including E. Argus, E. ocellata, E. zehra, and E. 

 Westermanii. 



No. 2, fossil earth from New Zealand, transmitted by our corre- 

 sponding member, Captain Hutton. This material was most 

 interesting, containing peculiar forms of Melosira and Achnanthes 

 in great abundance. Whether these species are new or not, remains 

 for further investigation. 



No. 3, from Calcutta. Tliis gathering contains Pleurosigina 

 reversum (Greg.) in considerable abundance. The form was de- 

 scribed by the late Dr. Gregory in his paper on the Clyde forms. 

 Onlj'^ four specimens were found by him, and in all cases the striae 

 were so faint that he was unable to ascertain their character. In 

 these specimens from Calcutta the striiB are distinctly marked and 

 transverse. 



Dr. Alexander Dickson exhibited embryos of Pinguicnla vulgaris 

 and P. grandiflora. He pointed out that the embryos of these species 

 agreed in having only one cotyledon, but that they presented marked 

 differences by which they might readily be distinguished from each 

 other. In P, grandiflora the base of the single cotyledon almost 



VOL. VIII. NEW SER. I 



