1913] CURRENT LITERATURE 243 
5 species of Podozamites (3 of which are new), and Coniferales (5 species, among 
them a new Cupressinoxylon). 
SEWARD,* in reporting upon a collection of fossil plants from the Wealden 
of Sussex, describes new species in Lycopodites, Selaginellites, Hausmannia 
(Dipteridineae), Pelletieria (a new genus of Schizaeaceae), Teilhardia (a new 
genus of ferns of uncertain affinity), Dichopteris, Conites (cones of uncertain 
affinity). In a general survey of the Wealden floras, the author concludes that 
“while there is a very close similarity between the Wealden flora of England and 
the corresponding floras in Eastern and Western North America, the number of 
cosmopolitan types is smaller than in the case of the Middle Jurassic floras.” — 
J. : 
Chondriosomes and myelin forms.—The problem of the chondriosomes, or 
mitochondria, is approached from a new direction in a short article by Léw- 
SCHINS? who happened to notice the formation of myelin forms from lecithin in 
a microscopic preparation. These myelin forms bore such a remarkable resem- 
blance to chondriosomes that Loéwscu1n made a careful examination of myelin 
forms secured from commercial lecithin. The following are some of the more 
important results: all the forms characteristic of chondriosomes were obtained 
and their size varied from structures easily seen with a low-power dry objective 
to those barely visible under the highest powers. In general, the size depends 
upon the mass of the material, the fineness of its division, and the chemical and 
physical characteristics of the surrounding medium; while the form is dependent 
upon the composition of the bodies, their surface tension, and the nature of the 
surrounding medium. It is to be noted that the elongated forms are found when 
there is streaming in the surrounding medium. The myelin forms may appear 
homogeneous or may show a finer structure, and the outer membrane may be’ 
forms arise, develop, and disappear. They may on and flow together, forming 
a thes (Chondriokonten), from which are developed granular 
eads (Chondriomiten), which may then break up into single granules (mito- 
antes. and te again may form into chains. One can observe directly the 
formation of diplosomes and their division into two granules. The myelin forms, 
like chondriosomes, may be fixed by chromic acid, osmic acid, or formalin, but 
are destroyed by acetic acid. 

%°Sewarp, A. C., Contribution to our knowledge of Wealden floras. Quart. 
Jour. Geol. Soc. 69: beni6. pls. I1-14. 1913. 
*7 Loéwscuin, A. M., Myelinformen und Chondriosomen. Ber. Deutsch. Bot. 
Gesells. 31: 7203-209. 1913. 
“myelin forms” is meant the emulsion forms which, under the action of 
emulsion-producing substances, form upon fatty acids. 
