i9i8. Irish Societies. 75 



DUBLIN MICROSCOPICAL CLUB. 



■March 13. — The Club met at Leinster House. The President (X. 

 CoLGAN, jNI.RT.A.) exhibited a series of sUdes illustrating the sclereids 

 or stone-cells occurring in the pulpy fruits of certain genera of Ericaceae. 

 These bodies varied in form from rods of slender, angulated outline to 

 plates of rounded or elliptic contour, suggestive of the dermal deposits 

 of the holothurians or sea-cucumbers, though in all cases destitute of 

 the perforations so characteristic of the "deposits" in this group of 

 echinoderms. While fairly constant in the range of outline for each 

 species, many different tvpes of these deposits occurred in the genus 

 Vaccinium, of which seven North American species were examined. 

 In the closely allied genus Gaylussacia, the American Huckleberry, two 

 species, G. frondosa and G. resinosa, were found to have these cells not only 

 distributed through the pulp of the berry, but forming a dense scaly coat 

 round the seeds. A very distinct type occurred in the berry of 

 Pernettya, a South American genus of Ericaceae ; and forms resembling 

 those of the North American Vaccinium erythrocarpmn and V. crassifoUinn 

 were found in the fruits of the [Mediterranean Arbutus Andrache and 

 A. Unedo. Even the smallest, those of Vaccinium pallidum, displayed 

 their striae quite clearly under a half -inch objective. There is obviously 

 a wide field open here for further investigation. 



Prof. G. H. Carpenter showed mounts of larval fiat-fishes illustrating 

 the translation of the eye from the one to the other side of the head during 

 transformation. 



J, N. Halbert showed an undescribed Lasioseius, a genus recently 

 established by Dr. Berlese in his revision of the Seius-group of the family 

 Gamasidae. The following is a brief description of the male, of which a 

 single specimen was found by Mr. A. D. [Michael on the seashore at 

 Swanage some years ago, and a second specimen occurred recently under 

 decaying seaweed on the rocky shore at Malahide. 



The shape is ovate and the size about 768^/, x 537/7. ; the dorsal surface 

 is finely punctured and reticulated. The species is chiefly remarkable 

 for the seven pairs of long spines on, or close to, the side margins, and 

 there are two more on the front margin of the body. These spine-like hairs 

 are very stout and smooth except at their extremities, which are flattened 

 and distinctly spinous. The V-shaped sternal plate has three pairs of 

 sharp side-processes and ends in a point ; the anal plate is small, with 

 emarginate sides and a long terminal hair. The peritreme is markedly 

 sinuate and opens a little in front of the last pair of legs. The mandibles 

 are small, with short side-processes. The legs, with the exception of 

 the first pair, are remarkably stout, and are armed on their upper surfaces, 

 with spines like those on the body ; the hairs on their under surfaces arc 

 sharply pointed. This distinct species may be called Lasioseius fucicola. 

 It will shortly be described in detail in a paper to be communicated to the 

 Royal Irish Academy. 



