1907] CURRENT LITERATURE 289 
In the latest note'’ GuIGNARD adds a considerable number of Rosaceae, of 
the tribes ae and Spiraeae, whose leaves and other parts furnish hydro- 
cyanic acid.—C. R. B. 
Sexuality of the Uredineae.—In 1904 BLACKMAN" showed that a peculiar 
process of fertilization occurs in the aecidium of Phragmidium violaceum, by 
which a nucleus from a vegetative cell of the mycelium migrates into a fertile cell, 
and thus brings about the condition of paired nuclei found by Sapprn-TRovuFFy'S 
to be quite universal in the teleutospore-bearing mycelium. Two questions 
naturally arise as a result of this work. First, since the aecidium of P. violaceum 
is of a special type, how far will this process of fertilization be found to explain 
the origin of conjugate nuclei in aecidia generally ? Second, what process takes 
place in those forms which have no aecidium? Both of these questions BLACK- 
MAN and FRAsER?® attempt to solve in a later contribution to the cytology of the 
Uredineae. In Uromyces Poae Raben. and U. Poarum Neil., both of which 
are eu-forms with typical aecidia, the migration of nuclei from one vegetative 
cell to another was observed in the tissue of the aecidium. These mi- 
grations were not so easily distinguished as in P. violaceum. In Melampsora 
Rostrupi Wagn., which has aecidia of the caeoma type, no fertilization was 
discovered, but there were some evidences that fertilization took place in the 
manner described by CHristMAN for Phragmidium speciosum. In Puccinia 
Malvacearum Mont., a lepto-form, the change from uninucleate to binucleate 
cells takes place in the hyphae of the teleutosorus, but the exact method 
could not be determined; neither could the transition be made out in the micro- 
forms P. ati i: C, VU. Scillarum Wint., and U. Ficariae Lév.—H. 
HASSELBRIN 
The filiform apparatus.—Striations on the micropylar portion of synergids 
were described in 1856 by ScHacut, who called them “fertilization threads” 
oe HorMEIsTER gave the name “filiform apparatus” (Faden- 
apparat); STRASBURGER in 1882 believed the lines or threads consisted of fine 
pores. A paper by HABERMANN”? now brings modern technic and modern lenses 
to bear upon the subject. The filiform apparatus, more or less developed, is 
characteristic of angiosperms generally. The apparatus arises by the transfor- 
———, Nouveaux exemples de Rosacées 4 acide cyanhydrique. Compt. 
Rend. Acad. Sci. Paris 143:451. Oct. 1. 1906. 
4 BLACKMAN, V. H., On the fertilization, alternation of generations, and general 
ree of the eadiee, Annals of Botany 18: 323-373. pls. 2I-24. 1904. 
15 SAPPIN-TRouFrFY, P., agg seires ieungelea ail sur la famille des Uredinées. 
Le Botaniste 5: 59-244. figs. 68. 
16 BLACKMAN, V. H., and ea Miss H. C. I., Further studies on the sexuality 
of the Uredinaceae. Annals of Botany 20:35-48. pls. 3-4. 1906 
17 HABERMANN, ALFRED, Der pouty in den eee der Angiospermen. 
Beih. Bot. oo 20: 300-317. pl. 13. 19 
