772 



SCIENCE. 



[Vol. II., No. 45. 



those regarding some of the red granites of Maine ; 

 for he has probably never seen them after their pol- 

 ished surfaces have been long exposed to the weather. 

 — {Proc. U. S. nat. mvs., vi. 105.) m. k. w. [481 



MINERALOGY. 



Cassiterite. — W. P. Blake notes tlie occurrence 

 of cassiterite as stream-deposit, as well as in place in 

 the Black Hills, Dakota. It occurs in a coarse crystal- 

 line granite, yielding sheets of mica of commercial 

 value, and large cleavage blocks of felspar. In addi- 

 tion, spodumene is found abundantly in gigantic crys- 

 tals. — (/Imer. Jo!(r(i. sc, Sept.) s. L. P. [482 



Lithiophilite. — Two analyses of this manganese 

 variety of triphilite are given by S. L. Penfield, — one 

 from a new locality in Norway, Me. ; the other from 

 Branchville, Conn. The analyses fully substantiate 

 the formula of the species LiMnP04, in which a part 

 of the manganese has been replaced by iron. — {Atiter. 

 Joini-n. sc, Sepf.) s. L. p. [483 



Augite. — Tlie calculation of several augite analy- 

 ses is given by C. Doelter, in which he shows, that in 

 addition to the usual meta-silicate, R"2Si..05, the alu- 

 mina and alkali, when i^resent in various amounts, 

 are united in molecules of the general formula, 

 K"E'".,SiO^, of which he recognizes the following 

 distinct molecules, wliich are isomorphous with each 

 other and with the meta-silicate R"oSi.,06: — 



MgAI,SiO„ MgFe"',SiOc 



Fe"AI.,SiO„ Fii"Fe"'„SiO„ 



C:iAl,SiO„ CaFi;"'„BiO„ 



Na.Al.SiOe Na„Fe"'„SiO„ 



(Min. petr. mitih., V. 22i.) s. L. p. [484 



BOTANY. 



Hybridization of Zea. — Dr. Sturtevant writes, 

 concerning the supposed direct manifestation of hy- 

 bridization in the fruit of the first year, " We have 

 as yet no station data whereby this belief can be veri- 

 fied." — {Eep. N. Y. exper. stat., i. 1SS3. ) w. t. [485 



Fed and unfed sundews. — Biisgen briefly re- 

 views tlie experimental efforts thus far made to de- 

 termine the value of animal food for carnivorous 

 plants, and gives the results of some feeding-e.xperi- 

 ments with Drosera rotundifolia carried on by him- 

 self at Strassburg. 



To avoid the inequality certain to exist in plants 

 gathered from their native habitat, containing unequal 

 quantities of reserve material, and of different ages, 

 Biisgen used seedlings, arguing that the slight weight 

 (.02 mgm.) of the seed, and especially of its nutrient 

 contents, renders the dry weight of all plants essen- 

 tially equal at the beginning of the experiment. By 

 averaging the results obtained from many plants, in- 

 dividual peculiarities could be eliminated for the most 

 part; and, by subjecting the seedlings to fluid-cul- 

 tures with different fluids, the necessity of nitroge- 

 nous compounds in the water absorbed by the roots 

 was susceptible of determination. 



All of these possibilities were not realized in the 

 exijerinients reported, which extended through two 

 seasons, since comparatively few plants were experi- 

 mented upon, and these were cultivated on cakes of 



peat of unknown composition, saturated with the 

 cultiu-e-fluid used. The results were measured by 

 the size and vigor of the grown plants, their fruitful- 

 ness, and, finally, the dry weight of all their parts. 



Without giving the details of the experiments, — 

 which, though not perfect, appear to be the most 

 satisfactory yet performed, — we may state that they 

 seem to show quite conclusively that plants of this 

 species, properly fed with animal matter (aphides) 

 through their leaves, are individually stronger, more 

 fruitful, and of greater weight, than those subjected 

 to the same conditions but unfed ; thus corroborating 

 the conclusions of Francis Darwin, Kees and Keller- 

 mann and v. Kaumer. It seems, however, as if the 

 organic nitrogen cannot wholly replace that derived 

 normally through the roots, but appears as useful 

 for the plant only when supported by a certain 

 quantity of nitrogenous salts (cf. Liebig, 'Die chem. 

 in ihrer anweud. auf agric. u. physiol.,' i. 4:30). — 

 (Bot. zeitunu, nos. 35, 3U.) w. t. [486 



ZOOLOGY. 



Animal chlorophyll. — Th. W. Engelmann main- 

 tains that the <liffuse green observed by him in 

 certain Vorticellas is genuine chlorophyll, and not 

 due to the presence of any vegetable matter. The 

 species was found near Utrecht, and is related to V. 

 camijanula. The green coloring is diffuse, but is 

 restricted to the ectoplasm. To study it, Engelmann 

 employed the bacteria method, and found that the 

 bacteria accumulated about the anitnalcule; whence 

 he concludes that the green produces oxygei\. Ex- 

 amined with the microspectroscope, the activity of 

 the green Vorticella, as measured by the gathering 

 of bacteria about it, varies in the same way, accord- 

 ing to the wave-length of the light in which the ani- 

 mal lies, as does the activity of vegetable chlorophyll 

 under corresponding circumstances. From these and 

 other observations, Engelmann deduces the existence 

 of true living chlorophyll, not of vegetable origin 

 in this j)rotozoon. The article is a contribution to 

 the controversy concerning the existence at all of ani- 

 mal chlorophyll. [Engelmann relies upon the distri- 

 bution of bacteria in the field of the microscope as a 

 test for the distribution of oxygen. It is obviously 

 hazardous to assign to living organisms whose pecul- 

 iarities are most imperfectly known the value of a 

 specific chemical test. We must look upon the ' bac- 

 teria method ' with suspicion, because the idea, which 

 is very ingenious, does not rest upon an established 

 certainty. {Re}).)] — (PfiiXijefs arch, physiol., xxxii. 

 80.) c. s. M. [487 



Morphology of the primitive streak. — Eepia- 

 choft' has confused the primitive mouth (lu'numd) 

 with the blastopore. Owing to this, he attempts to 

 disprove the connection of the primitive streak and 

 groove with the primitive mouth by insisting upon 

 the well-established point, that the blastopore is con- 

 nected only with the posterior end of the primitive 

 groove, overlooking the fact that the blastopore corre- 

 sponds only to the posterior part of the primitive 

 mouth, the edges of which unite all the way in front 

 of the blastopore to malce the primitive streak and 



