DUBLIN MICROSCOPICAL CLUB. 211 



of an intracystic growth, or " hernia of adenoid mammary tissue ;" 

 of a fibrous tumour ; of a round-celled sarcoma ; and of carcinoma 

 from eight different cases. 



Dublin Micboscopioal Club. 

 25M September, 1873. 



Sections of Miocene Zeolite-bearing Trap, exhibited.— Frof. Mac- 

 alister exhibited a sectiou of the Miocene Zeolite-bearing trap from 

 Trotternish, Isle of Skye, showing the relations of the Labradorite, 

 Augite, and Olivine crystals of which it is composed. 



Spectroscopic examination of Crystals from a Cactus. — Mr. Tich- 

 borne stated that, since the previous meeting, he had at Dr. Moore's 

 request, examined the crystalline masses, as they might be called, 

 found by him in a species of Cactus. These had proved themselves 

 to consist of oxalate of lime. When examined with the spectroscope 

 the calcium bands were given in a striking manner, showing the 

 value of this instrument for minute analysis. When the crystals 

 were ignited they gave white opaque particles without blackening ; 

 these were seen to effervesce when treated on the slide with acetic 

 acid. They were not soluble in acetic acid, but were so in hydro- 

 chloric acid, and the resulting solution gave a precipitate on the 

 addition of ammonia. They were evidently, therefore, crystals of 

 oxalate of lime. 



Exhibition of Algcefrom Hot-water Springs, Azores. — Mr. Archer 

 exhibited some further examples of algae and other organisms from 

 the Azores gatherings made by Mr. Mosely. Amongst these was the 

 alga ere now brought before the Club and spoken of as " Animated 

 Sand" (see Club Minutes of July, 1871). He showed, too, a 

 curious gemma-growth on a moss stem, resembling the ' radical 

 tubercles' (tubercules radiculaires, Schimper), but he hoped to 

 revert to this collection on a future occasion. 



2^rd October, 1873. 



Structure of Ganoid bone of Ganorhynchus Woodwardi, Traquair. 

 — Dr. Traquair exhibited a sectiou of the ganoid bone on the surface 

 of the fossil fish-snout, which he had recently described as Gano- 

 rhynchus Woodwardi. Though the fish belonged to the Order 

 Dipnoi, and not to the Ganoids proper, the section exhibited cha- 

 racters essentially similar to those found in the polished plates and 

 scales of many Ganoid fishes. When the section was taken the 

 bone was very thin, being only about -Jq" in thickness. It showed 

 first a thin superficial layer of structureless ganoine about yoVij" 

 thick ; through this the punctures of the surface opened into a set 

 of short vertical canals, widening downwards so as to assume a 

 somewhat conical figure ; these communicated with each other at 

 their bases, and also with the close, irregular network of Haversian 

 canals which ramified through the remaining inferior part of the 



