432 



SCIENCE. 



[Vol. I., No. 15. 



improved by grafting, and the company was conceded 

 half of the yield for the next twenty-flve years. Per- 

 mission was given to lay a narrow-gauge railroad 

 from Obok, at the head of the Gulf of Aden, past lake 

 Aussa, to Shoa, following up the left bank of the 

 'Ouache' (Hawash), where the construction would 

 be easy and cheap. — (Comptes rendus soc. geogr. 

 Paris, 1883, 36.) (The road projected would be at 

 least two hundred miles long, and partly in a very 

 unproductive country; so that, in spite of the present 

 activity of African development, this project can 

 hardly expect an early completion. ) — w. M. D. [888 



(AUatitic Ocean.) 



The Faraday Hills. — Dr. O. Kriimmel has dis- 

 cussed the Atlantic soundings published by the 

 Siemens Brothers (see 439), and shows that the 

 Faraday Hills (about lat. 50° N., long. 30° W.) are 

 very probably formed by submarine volcanic erup- 

 tion. The soundings are so numerous and exact, 

 that a trustworthy profile across the hills is con- 

 structed, exhibiting their surprisingly steep slopes 

 (13 to 17° on one side, and 35 to 25° on the other), and 

 revealing them as a mass about six miles broad at 

 the base, rising from a bottom 1,300 to 1,700 fathoms 

 deep to a summit about a mile broad in a minimum 

 depth of 630 fathoms. Tlieir form is therefore truly 

 volcanic, and their altitude approaches six thousand 

 feet. They are of rocky or stony surface, and have 

 no ooze characteristic of deep-sea bottoms. The 

 Flemish cape on the eastern slope of the Newfound- 

 land banks is also stony, but this is regarded as 

 a deposit of drift from melting icebergs. — {Ann. 

 hydrog.,lSS3,5,UQ.) w. M. D. [889 



The Triton in the North Atlantic. — A sound- 

 ing expedition on the British steamer Triton, under 

 direction of Mr. Murray, formerly geologist on the 

 Challenger, spent about a month in August and 

 September last in exploring the Atlantic from the 

 Shetland to the Faroe Islands, where, according to 

 previous explorations, a shallowing of the bottom, 

 named the ' Wyville-Thomson ridge,' separated the 

 deep cold water on the north at 32° F. from the 

 warmer bottom-water on the south at 47° F. In 

 the northern ijart of the ridge, a depression was found 

 with a depth a little over three hundred fathoms, 

 through which some of the arctic water may pass 

 southward. The shallower parts of the ridge, with 

 a minimum depth of two hundred and sixty fathoms, 

 is covered only with gravel and stones, and some of 

 the latter showed distinct traces of glacial action. 

 The fragments are of sandstone, diorite, mica-schist, 

 gneiss, limestone, etc. Several new species were 

 added to the faunae of the warm and cold areas first 

 described in the results of the Lightning and Porcu- 

 pine expeditions in 1808, 1869. — {Ann. hydrog., 1883, 

 194.) w. M. D. '890 



BOTANY. 



{Pktjslologioal.) 



Extravasation of water from leaves. — This 

 interesting phenomenon has been carefully examined 

 by Volkens, who, while adding little that is really 

 new, has shown the relations of the water-pores 

 to the underlying tissues in a large number of 

 families. It may be said, that, with three exceptions, 

 the points of secretion were confined, in all cases 

 examined, to the upper side of the leaf. The places 

 are always distinguished by color, swelling, or some 

 equally well-marked indication. The nuniber of the 

 pores is typical in many families and sections. — 

 {Jahrb. hot. gart. Berlin, IQUZyl&l.) o. l. g. [891 



Continuity of 'protoplasm in contiguous cells. 



— Hillhouse's method is a modification of Sachs's, and 

 consists in using dilute sulphuric acid on thin sec- 

 tions, following this by concentrated acid for several 

 hours, thoroughly washing with water, and finally 

 staining with ammonia-carmine. By this means it is 

 possible to break down cell-wall without disturbing 

 the protoplasmic threads. A similar process was 

 used by Gardiner in his study of Mimosa. — {Bot. cen- 

 iralbl., xvi. 1883.) G. L. G. [892 



Variable dichogamy. — Though as a general 

 rule the Indian corn (Zea) appears to be imperfectly 

 protandrous, — beginning to shed its pollen one or 

 more days before the stigmas of the same plant are 

 developed, but continuing the process for several days 

 afterward, — in no small number of instances tlie 

 dichogamy is reversed, so that the plant is strongly 

 protogynous, while it is sometimes synacmic, — stam- 

 inate and pistillate flowers maturing at the same 

 time. Tills, with the similar behavior of the perfect 

 flowers of certain species of Ribes, notably the golden 

 currant, shows pretty clearly how either sort of di- 

 chogamy may have originated in what were at first 

 synacmic species. — {Rural New-Yorker, April 14.) 

 W. T. [893 



Self -impotence of red clover. — For six years 

 Prof. Beal has been experimenting on tlie fruitful- 

 ness of Trifolium pratense, when self-pollinated and 

 when crossed by humble-bees. Though the results 

 obtained in the several years differ greatly, — from 

 absolute self-sterility to the production of two-thirds 

 as many seeds as by crossing, — they agree in showing 

 a marked increase of seed where bees have worked. 

 A source of error which tends to diminish the appar- 

 ent value of crossing is the impossibility of excluding 

 species of Thrips and other small insects by means of 

 the netting used to cover the plants for the exclusion 

 of bees, so that it is probable the degree of self- 

 impoten<;e is greater than appears from these experi- 

 ments. The general results may be gathered from 

 the appended table of ratios : — 



First year . 

 Second year 

 Third year 

 Fourth year 

 Fifth year 

 Sixth year 



Average 



First crop, 1.3 



Second " 0.0 



Not counted J 



100 (0:337). 

 rateiy (0:many}. 



100 



— {Rep. bot., Mich, agric. coll., 1881-82; Amer. agric, 



Jan.) w. T. , [894 



{Systematic.) 



Flora of Madagascar. — The most important nov- 

 elties among the Polypetalae of recent English col- 

 lections in Madagascar are described by Mr. J. G. 

 Balcer, including about 135 species. The woody char- 

 acter of the vegetation is remarkable, as shown by 

 this list, in which are 40 trees, and 64 shrubs and 

 woody climbers, against 31 mainly herbaceous peren- 

 nials and annuals. — • {Journ. Linn. sue. Land., March, 

 1883. ) s. w. [895 



New Bermuda plants. — The flora of the Ber- 

 mudas, like that of the Azores, is remarkable for the 

 almost complete absence of endemic species. With 

 the exception, perhaps, of the palms, as yet imper- 

 fectly known, the only peculiar plants are two that 

 have been recently described by Mr. Hemsley, and 



