1896.] Procecdino;s of Irish Societies, 109 



Dr. C. Herbert Hurst exhibited a pocket microscope made by Swift, 

 with an addition l)y Aylward. The instrnment is contained in a case 

 measuring 6^ inches by 2; inches by 2\ inches outside, and weighs, with 

 the case, i lb. 9 oz. When set up inclined for use with a zoophyte-trough 

 its area of support is a triangle, the sides of which measure 5 inches, 

 5 inches, and 6 inches respectivel}', and the height being only 7?, inches, 

 it possesses extraordinary stability and is particularly well adapted for 

 use at sea. Aylward's addition is a folding foot with an equilateral 

 triangular area of support, each side of which measures 4?, inches, fitting 

 the instrument for use in a vertical position for examining objects in a 

 watch-glass or on a slide. The fine adjustment screw is good, and the 

 instrument works well with powers from 4-inch to jV-iiich. 



Dr. Hurst also showed Ascetta primordialis, Hseckel, a specimen taken 

 with the dredge in Rhoscolyn Bay, Holy Island, Anglesey, May 25, 1890. 

 This exceedingly simple calcareous sponge, like another specimen taken 

 the same day, was found attached to the base of a tuft of AntennnJaria 

 antennina. 



Mr. Moore exhibited a pseudo-bulb of a species of Anguloa which 

 had been attacked by a Fungus. The Fungus had not yet been identified, 

 and the exhibit was to show the manner in which the pseudo-bulb was 

 attacked and destroyed. The inner tissues were gradually disrupted, 

 and at certain spots the hard epidermal tissues were burst outwards, 

 small irregular yellow masses of fungoid growth coming through the 

 openings. 



Corrigendum. — In report of December meeting, p. 51, lines 11 and 13, for 

 *' leaves " read " hairs." 



Bki<east Naturai, History and Phii^osophicai, Society. 



March 3. — The President in the Chair. Mr. CoNWAY ScOTT, CE., 

 lectured on " The Production of Ability." 



Bei,fast Naturalists' Fiei.d Ci,ub. 



February 26. — Geoi^ogicai. Section. — Mr. F. W. Lockwood 

 {President) in the Chair. Mr. J. O. Campbei.i<. B.E., gave an address 

 on the polarisation of light, and its application to micro-petrograph}'. 

 After a short preliminary explanation of the undulating theor}' of light, 

 the lecturer described the construction of the polariscope and the 

 manner in which the phenomena of polarisation arise. The methods 

 employed by petrologists to utilise polarised light in examining and 

 determining minerals was illustrated by blackboard diagrams, and the 

 practical application of the method to the study of crystals in rock 

 sections was explained. The paper was especially useful in anticipation 

 of Professor Cole's approaching course on field geology, when the 

 evenings will be devoted to a course on the study of rock-sections. 

 Rock-specimens were presented by Messrs. L. M. Bell, R. Bell, J. O. 

 Campbell, and the Honorar}' Secretary, 



