DUBLIN MICROSCOPICAL CLUB. 107 



scope, and explained the peculiarities of structure of this 

 genus. 



Minute egg-shaped deposits on shell of hen's egg. — Mr. Ro- 

 binson showed a portion of the shell of a hen's egg having 

 a group of little egg-shaped deposits on its surface, crowded 

 densely, which when viewed under a moderate power looked 

 wonderfully like a group of full-sized real eggs. Such little 

 deposits are occasionally seen on egg-shells. 



I^th August, 1873. 



Diatoms from Hot Springs of Azores. — Rev. E. O'Meara 

 brought before the meeting the general results of his examination 

 of some collections, from Hot Springs and some way-side 

 streams in Azores collected by Mr. Mosely, of the Challenger 

 expedition. The majority of the sediments, in the form of 

 solid lumps, from the former, contained no diatomaceous forms ; 

 however, one of these, described as found floating on the 

 surface of the Lake of Purnas, and producing a tough mass like 

 india rubber, but tenacious, contained diatoms in abundance. 

 The gatherings put up in bottles with spirit, whether from the 

 hot or cold water, produced diatoms, but of the common British 

 kinds. The collections which were of the most interest were 

 those from the very hot water, inasmuch as from such a habitat it 

 was to be expected some light would be thrown on the question 

 as to what high temperature can the lower organisms, animal and 

 vegetable, endure without detriment. The following diatoms, 

 amongst algae and some desmids, occurred in these hot-water 

 gatherings : — Synedra lunaris, Pinnularia gihba, Simantidium 

 arcus, Cymhella affinis, Gomphonema tenellum, G. dichotomum. 



AlgcB and Rhizopoda from Hot Springs of Azores. — Mr. Archer 

 showed several forms of Algae met with by him in the same 

 gatherings from A^zores collected by Mr. Mosely. Amongst 

 these were not only, as would be to be expected, phycochro- 

 maceoua forms, but also chlorophyllaceous, both filamentous 

 and unicellular. None of the former could be specifically identified, 

 as not any examples were seen in a fertile condition. Amongst 

 these were species of Conjugatae — Spirogyra, Mesocarpus (most 

 probably); various Desmidieae; of CEdogonieae — (Edogonium, Sulbo- 

 chcste; of Coleochseteae — Goleochcete ; oTScytonemeae —Tolypothrix; 

 of unicellular forms — Botryococcus JBratmii, and others ; various 

 Pediastreae ; also Ankistrodesmus falcatus. Not only were there 

 these algae, but the remains of various Rhizopoda occurred — Arcella 

 aculeata (so called), Trinema acinus, Muglypha alveolata, one or two 

 Difflugiae ; Dinohryon sertularia also occurred. Thus in this hot 

 water occurred so many forms equally met with in our home cool 

 pools. How high the temperature exactly of Furnas Lake, whence 

 these emanated, was not certain. Mr. Mosely, having at the 

 time no means of taking the temperature, seems to quote from 

 other sources the temperature of this lake as ranging from 22'^ 



