78 Field Naturalists'- Club — Proceedings. [voT'x'xxiii. 



REMARKS ON EXHIBITS. 



Mr. F. Chapman, in referring to his exhibit of the new 

 modelHng clay, " Modela," said that, upon placing a particle 

 of it in a little water, under a microscope with a high power, 

 he was greatly surprised to see a mass of well-preserved 

 coccoliths. These problematic algae, looking like tiny shirt- 

 studs, form the bulk of many chalks, nowithstanding the text- 

 book dictum that chalk is chiefly made of Globrigerina shells. 

 From the appearance of these coccoliths, and their abundance, 

 One might suppose them to come from the English chalk, 

 especially as they resemble those found in the whiting of 

 commerce, which is possibly the basis of this " clay." 

 Plasticine, under the microscope, differs entirely in being com- 

 posed of a starch, with comparatively huge grains and much 

 earthy material. He remarked that both of these modelling 

 clays are excellent for taking squeezes from fossils preserved 

 as hollow moulds. 



Mr. P. R. H. St. John called attention to his exhibit of a 

 sample of oil from Eucalyptus rostrata, var. horealis, R. T. 

 Baker, and stated that portion of the sample exhibited at the 

 June meeting, bearing the name of EucalypUts rostrata, had 

 been submitted to Messrs. Baker and Smith, of Sydney, with 

 very interesting results. They maintain that two forms of 

 Red Gum exist — i, Eucalyptus rostrata, Murray Red 

 Gum, and 2, Eucalyptus rostrata, var. horealis. River Red 

 Gum. The first yields an oil containing less than 10 per cent, 

 of cineol, with phellandrene, pinene, and a well-marked con- 

 stituent named aromadendral. The second contains nearly 

 70 per cent, cineol, with pinene, but no phellandrene or 

 aromadendral. So far no morphological di:fferentiation has 

 been detected between these two forms, which give such 

 definite results from the examination of the oils. They state, 

 also, that in time of drought cattle will eat the foliage of one, 

 but not the other. Mr. St. John expressed his thanks to the 

 above-named gentlemen for their kindness and trouble in 

 examining the sample of oil submitted to them. 



PAPERS READ. 



I. By Mr. Eland Shaw, M.R.C.S., F.E.S., entitled " Aus- 

 tralian Blattidae, Part II." 



The paper was read by Mr. J. A. Kershaw, F.E.S., who said 

 that he did not intend reading the whole of the article, the prin- 

 cipal portion of which was a detailed description of a male 

 specimen of the cockroach determined as Ischnoptera hrunneo- 

 nigra by Mr. J. G. O. Tepper in 1895. He said that the author 

 was doing excellent work in a slow and steady way among the 

 Blattidae. Much of his work was for the National Museum, 



