418 Dublin Microscopical Club. 



fered toto coelo in its zygospore therefrom. In that species, exhibited 

 to the Club at a former meeting, the zygospore is as yet unique 

 amongst Desmidiese : in figure it more nearly approaches that of 

 Cosmarium margaritifenim than any other ; but it is compressed, 

 not orbicular, and, besides, the superficial convexities are broader 

 and not so elevated, whilst its colour is of an orange or yolk-of- 

 egg colour, resembling, in fact, that of the spores of Volvox, and 

 wholly unlike that of any other Desmid. In the Staurastrum now 

 shown, however, the orbicular zygospore is beset with slender spines, 

 slightly dilated at the base, and minutely bi- or trifid at the apex, 

 and green in colour — in fact, belonging to a widely diffused type of 

 zygospore. Thus these two forms, however much they may exter- 

 nally resemble each other, declare themselves essentially distinct, 

 and that in a manner sufficiently pronounced. 



October 21, 1880. 



Lollgo magna. — Prof. Mackintosh exhibited a cross section of the 

 arm of the common Squid. The section showed that the axis 

 of the arm was occupied by a large nerve, which sends branches to 

 the pistons of the suckers ; in the sheath surrounding the nerve 

 were three bloodvessels, the coats of which were very distinct, and 

 which could be seen in longitudinal sections to send branches into 

 the substance of the nerve as well as to the surrounding muscular 

 bundles which composed the greater part of the arm, and were 

 disposed in various ways. The number of vessels varied from two 

 to five. Mr. Mackintosh had used both Eutherford's carmine and 

 Kanvier's picrocarmine as staining-fluids ; but the former gave the 

 best results. 



A new form of Potato-disease. — Mr. Greenwood Pim exhibited 

 specimens which had been given to him by Mr. Balfe, of the Eoyal 

 Horticutural Society, who had received them from Galway, where the 

 disease had materially injured the ci'op. On splitting the stems a 

 number of small roundish bodies about the size of small peas were found 

 imbedded in downy mycelium. These, when young, are white, but 

 turn black as they get older. A section through one of them shows 

 it to consist of a sclerotioid tissue of condensed mycelium, somewhat 

 like Ergot, but diff'ering from it considerably. Under present cir- 

 cumstances, and till some form of fructification is produced, it is not 

 possible to say to what group of Pungi it is to be referred, as the 

 old genus, to which it would formerly have been relegated (Sclero- 

 tium), has been abolished, it having been shown to consist of con- 

 ditions of various very distinct Pimgi. Mr. W. G. Smith, who has 

 examined specimens, coincides in this view. 



Section through Sebaceous Gland of Shin of Negro. — Mr. P. S. 

 Abraham showed a section through the sebaceous gland of the 

 skin of a negro. The gland was in the neighbourhood of a tubercle 

 of leprosy ; and it was imcertain how far its great size or hyper- 



