764 



SCIENCE 



[N. S. Vol. XXXVII. No. 959 



1903. Bd. III., Lief. 14. Pp. 123. Pis. IX. 



Stockholm. 1913. 



The recent renewed interest in Antarctic 

 exploration, the discovery of the South Pole, 

 the unfortunate fatality attending the English 

 expedition, etc., have focused attention on this 

 terra incognita. There is in this region so 

 much in the way of possibility as regards the 

 origins of floras and faunas, centers of distri- 

 bution, and possible migration routes, that 

 everything which tends to throw light on its 

 past life is likely to prove of absorbing inter- 

 est, and in this connection it is a pleasure to 

 note the appearance of Dr. Halle's splendid 

 memoir on the Mesozoic flora of Graham Land 

 which is the first Mesozoic flora known from 

 the Antarctic. Previous to the work of the 

 Swedish South Polar Expedition our knowl- 

 edge of the ancient Antarctic vegetation was 

 extremely limited. The present report is 

 based on a very large collection made, it is 

 said, under conditions of the greatest hard- 

 ship, by Dr. J. G. Anderson at Hope Bay, 

 Graham Land. The material came from a 

 single series of hard, dark, slaty rocks and is 

 regarded as Middle Jurassic in age. The flora 

 embraces 61 forms of which, however, nearly 

 20 have not been given specific names. They 

 are distributed among the several groups as 

 follows: Filicales 25; Cycadales 17; Conifer- 

 ales 16; unknown 3. It is of interest to note 

 that the Ginl^goales, which are so important 

 and varied an element in the northern hemi- 

 sphere, are entirely absent in the Antarctic, 

 as indeed they are in the Gondwanas of India. 

 Podozamiies, which is so abundant and vari- 

 able in the north, is absent from the Hope 

 Bay collection and is represented only by frag- 

 ments in the Indian localities. Cycads are 

 abundantly present at Hope Bay but they are 

 all small-leafed species, while the conifers 

 were abundant in materials but not well pre- 

 served. 



Although the author has made quite a num- 

 ber of new species — on the wise basis that it 

 is better to give a new name that may ulti- 

 mately become a s3monym, than to lump doubt- 

 ful material under an old name that later 



may have to be divided — there are no less than 

 22 species previously known. Of these, 9 spe- 

 cies are common to the Lower Oolites of Eng- 

 land, 8 to the Upper Gondwanas of India, and 

 5 to the Jurassic of California and Oregon, 

 with others which are scattered at various 

 well-known Jurassic localities. The close re- 

 lation existing between the Jurassic flora of 

 Graham Land and other contemporaneous 

 floras is certainly remarkable when consid- 

 ered in regard to its remoteness from these 

 floras. In the nearest continent, South Amer- 

 ica, there are no floras of any importance that 

 can be considered contemporaneous with the 

 Antarctic one. Dr. Halle concludes as fol- 

 lows : " Though the closest argument is with 

 the Jurassic flora of England, the resemblance 

 to the Indian Upper Gondwana flora is nearly 

 as great. The Hope Bay flora tends thereby 

 to lessen yet more the differences between these 

 floras and thus becomes another important il- 

 lustration of the uniformity and world-wide 

 distribution of Jurassic floras. This uni- 

 formity is all the more striking because of 

 the pronounced differentiation of the world's 

 vegetation into two dift'erent phyto-geograph- 

 ical provinces at the end of the Paleozoic, 

 which difference would appear to have become 

 almost extinguished in Jurassic time." 



E. H. Knowltok 



SPECIAL ASTICLES 



THE PHYSICO-CHEMICAL CONDITIONS OP ANES- 

 THETIC ACTION. CORRELATION BETWEEN 

 THE ANTI-STIMULATING AND THE 

 ANTI-CYTOLYTIC ACTION OF 

 ANESTHETICS 



The anti-stimulating action of lipoid-sol- 

 vent and other anesthetics is well known. Irri- 

 table tissues become temporarily irresponsive 

 when exposed to solutions of these substances 

 in certain concentrations, which must not be 

 too high — otherwise cytolysis results, or too 

 low — in which case irritability may be in- 

 creased instead of decreased. The precise na- 

 ture of the change in the irritable elements 

 conditioning the loss of irritability remains 

 obscure. The Overton-Meyer theory refers 



