FRAGMENTS OF SCIEXCE. 



575- 



at work upon it. The material was sent into 

 all Christian countries, and its name is found 

 in most European languages. Queen Eliza- 

 beth was vestita di tahi (Vargento et bianco 

 (dressed in silver- and- white tabby) when she 

 received the Venetian envoy Scaramelli in 

 1602. Samuel Pepys records of a certain 

 day that he put on his "false taby waiste- 

 coate with gold lace." And Miss Burney, on 

 the occasion of the birthday of the princess 

 royal, at Windsor, in 1786, appeared in a 

 gown of " lilac tabby." Dr. Johnson explains 

 in his dictionary that tabby is "a kind of 

 waved silk," and adds that the tabby cat is 

 so named from the brindled markings of its 

 fur. 



The "pine-barren region" of the At- 

 lantic coast, sporadic and narrow in New 

 England and Long Island, broadens as we 

 go south, and in the Carolinas often extends 

 to a distance of about eighty miles from the 

 sea. It has a flora of its own, and quite dis- 

 tinct from those of the hill and mountain re- 

 gions back of it. Mr. Thomas H. Kearney, 

 Jr., reports in the new periodical The Plant 

 World that he has found spots where a large 

 proportion of this flat-country flora occurs in 

 nooks of sandy ground hidden away among 

 the high regions of the Appalachians. Espe- 

 cially along the French Broad River, in East 

 Tennessee and western North Carolina, " there 

 is a notable incursion of plants usually con- 

 sidered typical of the coastal plain. In some 

 places these 'miniature pine barrens,' with 

 their growth of pitch and scrub pine and the 

 herbaceous plants that associate themselves 

 with them, push their way up on the lower, 

 near-by ridges, crowding among the oaks and 

 chestnuts that are the rightful tenants. Such 

 islands of coastal vegetation have been ob- 

 served at several places in this mountain 

 region." 



Every one is acquainted with those water 

 plants, the duckweeds, which appear to the 

 eye as small oval leaves floating on the sur- 

 face of ponds and streams, so closely packed 

 together as to form an apparently continu- 

 ous mass, often of considerable extent. Mr. 

 Charles Henry Thompson, who has made a 

 study of them, finds four well-defined genera 

 and about twenty eight species in their order, 

 the Lemnacece, distributed throughout the tor- 

 rid and temperate zones. In our range the 



four genera are represented by about thirteen 

 species and one variety, of which two species 

 and the variety are probably peculiar to it 

 alone, and ten are found only in the west- 

 ern hemisphere. There are difficulties in 

 classifying them, because the species have a 

 strong tendency to vary widely according to 

 the surroundings, and because the flowers 

 and fruit are only partially known in some 

 species and not at all in others. Then some 

 species may have two or three marked stages 

 of growth differing from each other so wide- 

 ly as to give rise to diiferent specific names 

 for each. In the third of these stages, which 

 the author calls the " resting stage," " winter 

 fronds " are formed, and the plant sinks to 

 the bottom, to rise again in the spring. Some- 

 what similar modified fronds are formed when 

 the ponds recede or dry up, to start out again 

 in healthy vegetation when the moisture re- 

 turns. 



NOTES. 



A VERY interesting excursion is offered 

 by La Nature to its subscribers, from the 4th 

 till the 16th of August, to the central pla- 

 teau of France, with its caves, gorges, and 

 mountain ascents. An itinerary has been 

 prepared contemplating a visit each day to 

 some of the remarkable and curiously at- 

 tractive spots in which the region abounds, 

 including an experience of subterranean navi- 

 gation in the Gouffre of Padisac, the Gouffre 

 of Reveillon, the mines and factories of 

 Decazeville, the buried forest of la Mougudo, 

 the viaduct of Garabit, the Course du Sauve- 

 terre, navigation of the Gorges of the Tarn, 

 the Grotto of Dargillan, and ascensions of 

 the Puy Mary, with lunch on the summit, 

 and of I'Aigoual. The entire cost of the 

 excursion, covering all ordinary expenditures, 

 is two hundred and fifty francs, or fifty dol- 

 lars, from Rocaraadour, where it begins, to 

 Vigan, where it ends, with reduced railroad 

 fares going and coming. 



Dr. Stuart Jeski.vs has not been satis- 

 fied with the adequacy of the Darwinian doc- 

 trine of descent and natural selection. He 

 is peculiarly struck with its failures to ex- 

 plain the infertility of hybrids and to fill the 

 gap between the invertebrates and the ver- 

 tebrates. After several years of independent 

 study and investigation of the subject, he 

 has published his conclusion in an elaborate 

 article in the Medical Age that " the verte- 

 brate organism, instead of being a single 

 organism which has been evolved from a 

 simple to its present highly complex form by 

 a gradual and cumulative differentiation, is 

 in fact a compound made up of two distinct 

 organisms constantly associated; . . . that 

 the divergence of the vertebrates from the 



