dlujlin microscopical club. 121 



Section of Spine of Temnopleurus torcumaticus, exlihitcd. — Mr. 

 IMackintosh exhibited a crof-s-section of tbe spine of Temno- 

 pleurus toreumatieus, Klein, which showed a single cycle of sohd 

 wedges of an irregular triangle-shape, intercalated between which 

 were narrow spokes of reticulated tissue running out from the 

 central pith. 



Elongate Unicellular alga, allied to the so-called Closterium 



ohtusum, Br^b. Mr. Archer drew attention to a unicellular 



form seemingly, so to say, congeneric with the so-called Clos- 

 terium obtusum (Breb.), and with those other allied forms Mr. 

 Archer has shown from time to time at the Club meetings, and 

 to which possibly should be added one or two usually, but doubt- 

 fully, referi'ed to Spirotsenia (including Spirotcenia obscura). 

 They are all elongate, like Closterium, it is true, with pale clear 

 spaces at the ends, but no moving granules, nor do the green 

 contents form longitudinal radiating laminae. The present form 

 was but very slightly arcuate, convex on one — the "upper" — 

 margin, straight, or nearly so, on the other — the " lower " — 

 margin, ends slightly tapered and bluntly rounded, the endo- 

 chrome forming lines running towards the ends. It was thus by 

 its tapering, not cylindrical, figure, and sides not parallel, as well 

 as by its smaller size, distinct from Brebissoa's plant. It more 

 resembled in form that shown at the November meeting in 1875, 

 but it was considerably smaller, and the contents wanted the 

 knob-like ending at either extremity, as well as the still single 

 granule suspended in the middle of the cavity. The cell-wall 

 showed here and there certain obvious thickenings, sometimes 

 imparting a certain amount of waviness to the outline. Cell- 

 division transverse, the two young cells remaining appended end 

 to end for some time. Whether the group of forms in question 

 should be relegated to the Desmidieas at all, and if so, as a dis- 

 tinct and new genus, any more than Ankistrodesmus, for 

 instance, would seem to amount to a begging of the question, 

 inasmuch as conjugation has not been observed in any one of 

 them, if, indeed, the brown so-called Cyliudrocystis occurring in 

 the pools on the flat moor above Lough Bray should not be 

 really placed therewith, and which has a smooth orbicular 

 Zjigospore. 



Winter state of Bryopsis plnmosa. — Dr. E. Perceval Wright 

 exhibited some living specimens and a long series of prepara- 

 tions illustrative of a very peculiar mode of growth he had 

 met with during the winter months in Bryopsis plmnosa. 

 In some cases the long and very tortuous and irregularly knobbed 

 cells were the much altered pinnse of the frond, which liad 

 fallen off and then vegetated in this manner ; in other cases these 

 were outgrowths of the base of the frond. In several instances 

 these winter growths assumed the appearance of having 

 oogonia, as in Vaucheria, but in no one instance was a true re- 

 production seen, and after months of careful watching the speci- 

 mens were destroyed by an unknown parasitic algal form. It 



