NA TURE 



[Jaxuarv 5, 1905 



In the Zoologist for December Mr. A. H. Patterson 

 records a number of more or less remarkable specimens of 

 fishes captured off Great Yarmouth during; the year. 

 Several examples of flat-fish with the two sides of the 

 same colour are recorded, a plaice of this type being further 

 remarkable from the fact that the dorsal and anal fins 

 united beneath the tail. In a second article Mr. G. 

 Dalgleish directs attention to the recent migration into 

 India of birds native of eastern Central Asia — notably the 

 mandarin-duck. 



The October issue of the Proceedings of the Philadelphia 

 Academy contains two papers devoted to the histology and 

 early development of invertebrates. In the first Dr. J. A. 

 Nelson discusses that puzzling creature Dinophilus, referred 

 by some authorities to the turbellarians, and by others to the 

 annelids. If the " trochophore " be regarded as a larval 

 form common at least to all annelids, the development of 

 Dinophilus cannot be considered as primitive. Rather it 

 may be looked upon as an annelid the larval stage of which 

 has become one towards which development tends, and 

 which has consequently become specially modified. In the 

 second of the two papers Mr. T. H. Montgomery gives the 

 results of his investigations into the development and 

 structure of the larva of the parasitic thread-worm 

 Paragordius. 



The December issue (vol. vii.. No. 2) of the Journal of 

 the Marine Biological Association of the United Kingdom 

 contains a full list of the marine invertebrate fauna of 

 Plymouth, compiled from the records of the association. 

 An excellent map of the Plymouth district accompanies the 

 list, together with notes on the various dredging-grounds 

 and their characteristic zoological products. Some of these 

 grounds, which formerly yielded rich harvests, have been 

 more or less completely spoiled by being made the receptacle 

 for rubbish and refuse from the neighbouring towns. 

 Attention is directed to the large number of species of 

 marine organisms attacking the limestone of which the 

 Plymouth breakwater is constructed. To such an extent, 

 indeed, is the stone eaten into by these creatures that con- 

 siderable damage is done to the structure, and constant 

 repairs are rendered necessary. 



We have received copies of three papers by Dr. J. E. 

 Duerden dealing with the morphology, development, and 

 relations of corals and sea-anemones. Their titles are 

 respectively "The Antiquity of the Zoanthid Actinians " 

 (Rep. Michigan Ace, No. 6, pp. 195-S), " Recent Results 

 on the Morphology and Development of Coral-Polyps " 

 (Smithson. Miscell. Contrib., vol. xlvii. pp. 93-101), and 

 "The Morphology of the Madreporaria," No. 5 (Biol. 

 Bull., vol. vii., No. 2). The main thesis of the first two 

 papers is that, since ordinary hexamerous coral-polyps differ 

 from sea-anemones to a great extent only by the absence 

 of a skeleton, and the presence of such skeleton is a 

 secondary development, the second group must be older 

 than the first. From this basis it is argued that the 

 tropical polyps known as zoanthids, which differ in regard 

 to the number of their septa from the hexamerous group, 

 bear a similar relationship to the Palaeozoic tetramerous 

 " rugose " corals, and are consequently of still more ancient 

 origin. In the author's own words, " The Rugosa and 

 ZoantheEE undoubtedly constitute a common group of 

 skeleton-forming and skeletonless polyps, just as do the 

 modern Madreporaria and ordinary hexamerous Actiniaria. " 



Three papers by Dr. R. Broom on the fossil reptiles of 

 South .Africa and their relationship to manmials appear in 

 vol. XXV., part iii., of the Transactions of the South African 

 NO. 1836, VOL 7 1] 



Philosophical Society. In the most important of these the 

 author discusses the origin of the mammalian carpus and 

 tarsus. After a brief review of the nature of these two 

 portions of the skeleton in other groups, Dr. Broom points 

 out that in dicynodonts and theriodonts the mammalian 

 appro.ximation is most marked. To quote his own words. 

 In these latter we find more or less approximation to the 

 mammalian type, but if we take into consideration the 

 extreme mammalian specialisation — the presence of a large 

 tibiale and fibulare, with a centrale which is not in the 

 centre but comes between the tibiale and the first tarsale, 

 then we are driven to the conclusion that the mammalian 

 ancestor must have been a dicynodont, a theriodont, or a 

 form belonging to a closely allied order. From the ex- 

 amination of the skull we have good reason to believe that 

 the ancestor was a theriodont, and the evidence of the 

 tarsus fully confirms that drawn from the skull and other 

 parts of the skeleton ; and the carpus, while it does not add 

 any very strong evidence, certainly does not afford any 

 evidence that is not in harmony with this conclusion." 



A REM.ARK.ABLE instance of what the author thinks may be 

 true mimicry among plants is described by Dr. R. Marloth 

 in the Transactions of the South African Philosophical 

 Society, vol. xv. p. 97. Years ago, it appears that the 

 traveller Burchell picked up on stony ground an object he 

 mistook for a pebble, but which on exaimnation proved to be 

 a plant of the genus Mesembrianthemum. Both in colour 

 and in form this plant, previously named M. truncatum, 

 presented a remarkable resemblance to the stones among 

 which it grew. A second species, .U. bolusi, growing on 

 the hills around the Karru, generally produces two leaves 

 about the size of a duck's egg, which have a surface like 

 weathered stone, and a brownish grey colour tinged with 

 green. In this state it closely resembles the surrounding 

 stone, although for a short time its bright yellow flowers 

 render it conspicuous enough. M. nobile is very similar. 

 A fourth species of the same genus, together with 

 Anacampseros papyracea (in w'hich the leaves are covered 

 with white papery stipules), resembles the quartz pebbles 

 among which it gro\vs. In the author's opinion, M. bolusi, 

 M. nobile, and perhaps M. truncatum (which, unlike some 

 of the other plants mentioned, do not change their 

 characters under cultivation), may afford instances of true 

 mimicry, or " homoplasy. '" 



We have received a report on forestry in the Transvaal 

 by Mr. D. E. Hutchins, conservator of forests. Cape Town. 

 The report deals with the immediate necessity for the 

 afforestation of those large tracts of land in the colony which 

 are unsuitable for agriculture. The importance of forestry 

 in the Transvaal cannot be over-estimated, as a perusal of 

 this report will show. After a tour of inspection, Mr. 

 Hutchins has been able to indicate in his report the organ- 

 isation and equipment necessary for the scheme. .\ list of 

 trees suitable for cultivation in the Transvaal is given, 

 together with short notes on their sylvicultural character- 

 istics and uses. It may be interesting to mention that the 

 common ash, Fra.xiniis excelsior, does not thrive in the 

 Transvaal. 



Messrs. F. Darton and Co., St. John Street, E.C., have 

 submitted to us a very handy and portable little instrument, 

 the " Piesmic " barometer, invented by Mr. A. S. Davis. 

 It consists of a glass tube about seven inches long, bent 

 in the form of a syphon, the longer arm being of strong 

 capillary tubing of one-tenth inch bore, the shorter arm 

 being of thin quill tubing. The end of the longer tube 

 opens into a small cast iron cistern, containing mercury ; 



