1 8 The Irish Naturalist. [Jan. 



them. These ticks are believed to live on plants of various kinds, but 

 wherever opportunity offers, they attach themselves to an animal body, 

 and suck blood voraciously. The mouth-organs, adapted for this pur- 

 pose, consisting of a pair of maxillae united to form a channeled 

 rostrum with toothed edges, and a pair of retractile chelicerse with com- 

 plicated barbed processes at the extremity, were shown under a high 

 power. Mr. A. D. Michael has kindly confirmed the identification. 



Professor GRENVII.1.E C01.E showed rhyolite-obsidian from Sandy 

 Braes, Co. Antrim, containing a crystal of hypersthene. The minute 

 structure of the glassy ground shows a delicate intermingling of little 

 rods, each formed of a row of globular crystallites. These are excellent 

 t)^pes of what Vogelsang called "margarites," from their resemblance to 

 strings of pearls. In this slide a strongly pleochroic rhombic pyroxene 

 (hypersthene) occurs. This mineral has not previously been recorded 

 from the Antrim rhyolites, and has possibly in this case been picked up 

 from a more basic lava. 



Mr. Greenwood Pim exhibited Tuberculina persicina, a curious parasitic 

 fungus growing on another fungus {Coleospofium tussilaginis) on leaves of 

 Tussilago at Brackenstown, near Swords. It forms compact little 

 cushions, surmounted by minute spores, and these cushions are seated 

 on the Coleosporiwn pustules. In Plowright's book on the Uredines it is 

 described as parasitic on the ALcidhim which occurs very abundantly on 

 Tussilago in spring, so that it also occurring on the Coleosporium is worth 

 recording. The plant is very readily passed over as a specimen of the 

 host fungus partially decayed. 



Prof. T. Johnson exhibited Melobesia confinis, Crn., a calcareous red 

 alga, growing on Corallina officinalis ^ on which, as also on limpet shells, it 

 forms small slightly thickened hard swellings. A preparation showing 

 the characteristic bisporous tetrasporangia and the vertically elongated 

 thallus-cells was exhibited. The material was gathered by the exhibitor 

 in 1891, at Frenchfort, Co. Mayo, when with Mr. Green in ss. 

 •'Harlequin " (R.D.S. Fishery Survey). M. confinis is recorded hitherto 

 from the coast of Brittany only. 



Mr. M'ARDiyE exhibited a specimen of Riccardia latifrons, Lindberg, 

 bearing the large perianth and capsule, with the andrcecium at the base 

 of the perianth, showing the paroecious character of the plant. The 

 specimens were collected in I^ord Howth's demesne last March. This 

 rare liverwort was first detected by Professor Lindberg, who collected 

 it at O'Sullivan's Cascade, Killarney, in company with the late Dr. D. 

 Moore, in 1873. It is an addition to the Co. Dublin list of Hepaticae. 



Mr. H. Lyster Jameson showed feathers from the base of beak of 

 adult and immature Rooks, showing the frequent presence of unpig- 

 mented feathers in the young bird, and the aborted or abraded feathers 

 in this region in adult Rooks, which gives the well-known appearance of 

 a bare patch round the base of the bill. Mr. Jameson referred to the 

 theory that these feathers are mechanically rubbed away by the Rook 



