Oct. 1, 1S70.] 



HARDWICKE'S SC IEN CE-GOS SIP. 



235 



MICROSCOPY. 



Fern Starch, &c— In the Proceedings of the 

 Geological Society for August is a paper by Mr. 

 W. Carruthers, iu which the following observations 

 are made on the occurrence of starch and the my- 

 celium of a fungus in a species of fossil fern allied 

 to Osmunda. " Not only are all the cells aud vessels 

 intact, but even the starch granules, which abound 

 in the parenchyma of ferns, still fill the cells in 

 which they were originally formed: or rather, I 

 should say, the silica by which they are replaced, 

 and which assumes their form, is there. In the form 

 of the granules, and in the method in which they are 

 packed in the cells, the fossil agrees exactly with 

 the recent species. Many of the cells contain the 

 mycelium-threads of a parasitic fungus, which are 

 inarticulate, aud probably belong to the genus 

 Peronospora, one species of which is too familiar 

 from the injury it has brought on the potato crops. 

 The dead stem of the fossil must have been at once 

 attacked by this parasite ; it could never have been 

 desiccated, as the most delicate tissues are perfectly 

 preserved. Buried in the moist clay, the silica 

 must have speedily replaced the organie tissues, 

 before the most delicate cells, the mycelium-threads, 

 or even the starch granules, were disorganized." 

 Without intending to insinuate anything derogat ory 

 to Mr. Carruthers' powers of observation, I should 

 be glad to learn what is the evidence that the 

 granules observed by him are really starch granules ? 

 Was there a hilum present, or concentric lines ? Or 

 was it a supposition ? Of course the iodine test and 

 the polaviscope were useless upon silicified (?) 

 starch. Also, what grounds are there for believing 

 that the mycelium of the fungus was that of a 

 Peronospora ? Hitherto no one has been able to 

 determine the genus of a fungus from the mycelium. 

 Moreover, can Mr. Carruthers name any other Pero- 

 nospora which is not developed upon living plants ? 

 —S. T. 



Jutland Deposit.— Some of the forms of Dia- 

 tomacese found in this remarkable deposit are de- 

 scribed and figured by Mr. E. Kitton in the current 

 number of the Journal of the Quelcett Microscopica I 

 Club, being the substance of a paper read by him at 

 one of the recent meetings. The species of Trinacria 

 and Hemiaulus are beautiful, and of considerable 

 interest. Slides of this deposit, prepared by Herr 

 Moller, were some time since introduced into this 

 country for sale, and at once became popular amongst 

 microscopists. 



Spontaneous Generation.— Mr. P>. T. Lowne 

 read an important and interesting paper on this 

 subject at the meeting of the Quekett Club on the 

 23rd September, during which he described experi- 

 ments, conducted by himself, demonstrating that 



boiling does not destroy the germinating powers of 

 the spores of fungi. The paper was succeeded by 

 an animated discussion, in which the president, 

 Professor Lionel Beale, took part. 



Hair of Maurandya.— I am not much of a hand 

 at drawing, but have sent a sketch 

 of the hairs on the seed-vessel of 

 the Maurandya, which I think are 

 worth notice among the hairs of 

 plants; the stem is transparent, 

 and the knob at the top is yellow ; 

 the stalk has a quantity of granules 

 of some kind in it, and it seems to 

 contain a good deal of oil. The 

 seeds are curious irregular-shaped 

 bodies, spiny, like the mallow pollen 

 when green. The plant is a beau- 

 tiful purple-flowered creeper. I 

 shall be happy to forward some 

 seeds to any one who would like to 

 have them, and will exchange any 

 slide for them— S. T. S. 



Scale of Crucian Carp {Cy- 

 prinvs carassius). — This is a verv F } s ;. 200, Hair 



. ,. it.- •'of Mdurtnidyti 



interesting addition to the series magnified. 

 of fish-scales which have appeared 

 in this journal. It was taken from the side of the 

 fish, and appears to differ from those on other 

 parts, by the channel running downwards from the 



Fig. 201. Scale of Crucian Carp (Cyprinns carassius). 



centre of the scale, and terminated by a rounded 

 orifice. These scales are apparently in a line along 

 the side. 



Alchemy superseded.— Henry Cockeram, in 

 his English Dictionary (edition 1655) thus describes 

 TJlex: "An herb like rosemary, which draweth gold 

 to it." The same writer says of Yarrow : " An herb 

 wherewith Achilles is said to kill or cure Telephus." 

 These extracts speak for themselves.— R.T., 31. A. 



