1906] CURRENT LITERATURE 235 
Spore formation in Botrychium.—-The development of the spores and the 
behavior of the tapetum in Botrychium virginianum are described by STEVENS.34 
Carorrr had already published an essentially identical account of the tapetum.34 
STEVENS’S term fapetal plasmodium seems to be a suggestive and convenient 
name for the peculiar tapetal mass as it appears in Botrychium and many other 
pteridophytes. The behavior of the kinoplasm and trophoplasm during the 
formation of spores from the mother cell indicates that these two plasms are 
interchangeable, each being able to become transformed into the other.—CHARLES 
J. CHAMBERL 
Dichotomous leaves in Cycas.—SEWARD®5 has called attention to the dichot- 
omous leaves of C. Micholitzii, a subterranean-stemmed species from Annam. 
Most of the pinnae are repeatedly dichotomous, but the terminal pinnae are 
simple and similar to those of other species of the genus. It seems that dichot- 
omous pinnae in the cycads were first noted by Moore in the Australian Macro- 
zamia heteromera. The author suggests the possibility that the usual simple 
pinnate type of the cycadean leaf “may be the result of reduction from an older 
type characterized by the more primitive dichotomous habit.”—J. M. C. 
Diatomin.—Kout was incited by the papers of Moxiscu?® and Tswerrs? 
to reinvestigate the coloring matter of diatoms,3® having denied in his work on 
carotin the existence of a special pigment, ‘“‘diatomin.” He now finds that 
his conclusion was correct as regards any special “diatomin; ” but the pigment 
absorption spectrum as in higher slain being ae pre esent. "The leucocyan 
of MouiscH he does not find. The yellowish or brownish hue of the diatoms 
is due to the prevalence of carotin as compared with the higher plants.—C. R, B 
Germination in Ophioglossum.—The difficulty and the desirability of secur- 
ing the germination of the spores of the pteriodophytes with tuberous gameto- 
phytes are well known. CAMPBELL announces (Annals Bot. 20: 321) in a brief 
note that he has secured germination in certain Javanese species of Ophioglossum. 
In every case the characteristic endophytic fungus was present beyond the 
three-celled stage. In one case a gametophyte of thirteen cells was found; but 
no stage between this and mature gametophytes were secured.—J. M. C. 
BR ee ee 
33 STEVENS, W. pore formation in Botrychium virginianum. Annals of 
Bot. 19: dae nh — 1906. 
*#Carprrr, I. D., The development of the sporangium of Botrychium. Bor. 
Gazerre A ioe "pl. 9. 1905. 
8s SEWARD, A. C., Notes on Cycads. Proc. Cambridge Phil.-Soc. 13: 293-302. 
1906. 
3° Mouiscn, H., Bot. Zeit. 63": 131-162. 1905. 
37 Tswetr, M., ibid. 273-278. 
* Kout, F. G., Die Farbstoffe der Diatomeen-Chromatophoren. Ber. Deutsch. 
Bot. Gesells. 24:124-134. 1906 
