June 3, 1904.] 



SCIENCE. 



857 



with the least resistance. This may be termed 

 the normal cross-section. 



The shape of this normal cross-section is 

 expressive of a well-ordered interior arrange- 

 ment of the ilowing mass; in other words, it 

 indicates a definite organization of the stream. 

 All streams should be considered as constantly 

 endeavoring to organize; the more efiicient 

 their organization, the more economical their 

 flow. 



An analysis of the mode of flow was 

 advanced many years ago by D. T. Smith in 

 an essay on the ' Law of the Double Helix.' 

 This theory was briefly outlined as not only 

 affording a probable explanation of the man- 

 ner of organization, but also satisfactorily 

 accounting for the tendency to produce nor- 

 mal cross-sections of the shape described. 



Whether this theory be accepted or not, the 

 fundamental principle of organization stands 

 unchanged. The tendency to evolve normal 

 cross-sections is alone sufficient to establish it. 



The application of this principle to the 

 study of stream and glacier channels could 

 not be considered for lack of time. 



Alfred H. Brooks, 



Secretary. 



THE BIOLOGICAL SOCIETY OF WASHINGTON. 



The 386th regular meeting was held on 

 Saturday evening, April 16, 1904. Carleton 

 E. Ball exhibited specimens of the dead nettle 

 (Laniium amplexicaule) showing cleistogam- 

 ous flowers which are produced abundantly in 

 early spring. Later in the spring the large 

 elongated open flowers are produced and the 

 cleistogamous form disappears. 



William E. Maxon spoke on ' Some Termite 

 Nests of Jamaica,' describing three nests col- 

 lected for the Smithsonian Institution in the 

 vicinity of Hope Gardens, Jamaica, in the 

 spring of 1903, and giving general notes (il- 

 lustrated by photographs) on the occurrence 

 and habits of Eutermes ripperti, the most 

 common species of the island. Occupied 

 nests, being the most perfect, were secured by 

 poisoning several colonies of the insects. The 

 nests secured were all of this species, which 

 occurs abundantly in the lower dry limestone 

 hills up to an altitude of 2,000 feet. They 



are built without much discrimination upon 

 the ground, in trees, upon old logs, walls, etc. 

 The exterior of the nest consists of a thin 

 granular, delicate fluted covering, very ranch 

 more delicate than the darker honeycombed 

 interior portion and very readily separable 

 from it. The largest of the nests collected 

 was exhibited, and also a queen cell and alco- 

 holic specimens of queens, workers, nasuti 

 and other forms of the insects. Notes on the 

 life history of Eutermes ripperti contributed 

 by E. A. Schwarz were also read. 



Vernon Bailey spoke on ' A Simple Method 

 of Preserving Tracks ' ; and exhibited a speci- 

 men of a mold of a wolf's track. A fresh 

 track of a wolf was found in moist sand and 

 melted paraffin from an ordinary candle was 

 poured into it, producing a characteristic 

 mold. 



E. S. Steele gave an account of an investi- 

 gation approaching completion of the globose- 

 headed Laciniarias, i. e., of the group of plant 

 species which have been included under the 

 name Laciniaria (or Liatris) scariosa. The 

 investigation has had the benefit of ample 

 material, comprising, besides that contained in 

 the National Herbarium, numerous loans from 

 institutions and individuals, and representing 

 the territory from Maine to Florida, Texas, 

 the Eocky Mountains and Saskatchewan, the 

 Minnesota region being specially rich. Eefer- 

 ence was made to the few hitherto published 

 names applicable to this material. The char- 

 acters upon which group and specific distinc- 

 tions must turn were noted and illustrated by 

 drawings, the involucral bracts and the foliage 

 being the most important. The species, of 

 which there were declared to be not less than 

 sixty, were stated to fall into three fairly dis- 

 tinct groups. Mounted specimens of a num- 

 ber of the species were exhibited. 



E. L. Morris read a paper on the 'History 

 and Knowledge of the Bush Morning Glory 

 and its Eeproduction.' The species was first 

 collected in 1820 and reported as annual. 

 Later it was collected many times, and occa- 

 sionally with enormous perennial roots which 

 sometimes weighed as much as 200 pounds. 

 Its reproduction is commonly by seed, but 

 another method was mentioned not before re- 



