HARDWICKE'S SCIENCE-GOSSIP. 



179 



a sparrow's, and I have another less than these. I 

 have some eggs of chaffinch, and blue tit, as small as 

 the egg of golden-crested wren (P. cristatus) ; and 

 an egg of linnet (C. eannabina), sent to me last year 

 from near Lancaster, is the smallest egg I possess — 

 being considerably less than the gold crest's. I have 

 seen several very small eggs of pheasant (P. colchicus) 

 one I have is about the size of a robin's egg. 



I have penned the above imperfect remarks in the 

 hope that they may interest your correspondent 

 S. Dewan, and others who take an interest in this 

 matter, and I shall be glad if any one will give any 

 instances that may come under his observation of 

 the occurrence of "dwarfs" in any other species 

 than those I name — or of any superstitions connected 

 therewith, other than those already noticed. 



R. Standen. 



Goosnargh, Preston, Lanes. 



MICRO-GEOLOGY. 



BY the kindness of W. H. Shrubsole, Esq., F.G.S., 

 I have been favoured with the opportunity of 

 seeing his most recent discovery, mineralised diatoms 

 in the London clay, which has greatly interested me. 

 The labours of that gentleman are too well known to 

 require comment, even if such were becoming, while 

 the fossilised remains of past generations in such 

 numbers by him are before us as the result of his 

 elaborate researches. The older geologists did much 

 in their way with the organic remains of the Tertiary 

 deposits, and not a little has appeared in the pages 

 of Science-Gossip by Taylor and others, on 

 various occasions, to direct attention and to facilitate 

 the study of minuter and more easily destructible 

 forms. It is possible that as investigation proceeds, 

 other forms of long absent creations than those now 

 recognised may yet be discovered, and in such a 

 state of fossilisation as of which we have no previous 

 experience, and that certain structural peculiarities 

 and natural processes may thereby become better 

 studied and understood. Mr. Shrubsole has explored 

 a zone of clay of over one hundred miles in extent, 

 therefore we may hope to have at an early future 

 some further interesting and useful additions to our 

 present knowledge of this important formation. 



I am not aware of any instance in which the 

 Diatomaceae have been previously discovered in the 

 state in which they are now found. Generally, those 

 fossilised bodies so called, are presented to us in their 

 primary siliceous condition, and more or less entire, 

 and, as a rule, in respect of their state we distinguish 

 but little difference between them and their more 

 recent representatives of our own time. With 

 those of the London clay, however, this is not so, 

 for the inorganic constituents appear to have under- 

 gone an important chemical change, as is seen by 

 analysis, and the original organism is represented 



by a most brilliant metalliferous deposit. There 

 was a time when the nature of the cell was a 

 subject of much dispute, and numerous were the 

 speculations respecting it, but now, were there but 

 a shadow of a doubt respecting it, such questions 

 would be immediately set at rest, since the optical 

 characters of the minutest details have become the 

 more prominent and conspicuous in proportion to the 

 deposition of metal upon it, while the depressions, 

 as they are called, are represented as apertures, or 

 foramina. The valves, consisting as they now do of 

 pyritic iron and an infinitesimal quantity of organic 

 matter, will, as I think, become a source of great 

 attraction to t the exhibitor. In brilliancy they are 

 equal to the most striking of the ores, and their 

 novelty must excite the curiosity and admiration of 

 all lovers of the beautiful. They are well rendered 

 by a condensed light from above, and by moderately 

 low powers, but they may be studied with the \. 

 They are, moreover, among the few subjects suited 

 to the performance of the "Smith's Vertical Illu- 

 minator," under which, and the \ inch, they are 

 gorgeous. But to the student of micro-geology they 

 will afford a still higher pleasure, and I have no doubt 

 that ere long the London clay will have become a 

 comparatively new and fertile field of research. 



J. Fedarb, B.E. 



HETEROMORPHIC ORCHIDS. 



PERHAPS in no members of the vegetable 

 kingdom is the remarkable phenomenon of 

 heteromorphism more distinctly exhibited than in the 

 two peculiar and interesting genera of Orchids, 

 Catasetum and Cycnoches. Observers have from time 

 to time recorded the appearance in some species 

 (chiefly Catasetums) of certain strange departures from 

 the typical structure of the floral organs accompanied 

 by the normal flowers of the species and several 

 intermediate forms all of which were in some 

 instances borne upon the same inflorescence. The 

 first who recorded one of these extraordinary occur- 

 rences was Sir R. Schomburgk, who contributed to 

 the Linnean Society a paper describing an orchid he 

 had found in Demerara which bore on one spike 

 flowers of what had been supposed to be three 

 distinct genera, viz., Catasetum, Monachanthus, and 

 Myanthus. He further observed that although the 

 Catasetum produced seeds freely, the Monachanthus 

 was uniformly sterile. This account was published in 

 the Linnean Society's Transactions (vol. xvii.) and 

 attracted the attention of botanists and naturalists 

 generally, but from its singularity was received by 

 many somewhat incredulously. Plowever, in Novem- 

 ber, 1836, a plant of Myanthus cristatus in the garden 

 of the Duke of Devonshire at Chatsworth also 

 produced flowers of Monachanthus and Catasetum 

 similar to the plant described by Sir R. Schomburgk. 



