382 BOTANICAL GAZETTE [JUNE 
because imbedded in the horny endosperm which is not easily 
penetrated by killing fluids. In 4. Americanum, as shown by 
Jeffrey, the suspensor is much larger. Figs. 87 and 88 represent 
sections of two embryos from this plant. These show well the 
large umbrella-like suspensor. The lowermost lobe is the one 
which develops the embryo, but if any of the other lobes of the 
suspensor should become separated from the main mass it would 
probably develop an independent embryo. This would be only 
an accidental case, however, as may frequently happen in any 
embryonic tissue. This is probably not to be regarded, there- 
fore, as an ordinary case of polyembryony, but the large su-- 
pensor is especially developed as an embryonic absorbent 
organ, as suggested by Coulter (9). 
COLUMBUS, OHIO. 

LIST OF PAPERS ESPECIALLY CONSIDERED, 
1. ATKINSON, GEORGE F.: Studies on reduction in plants.. Bot. Gaz, 28:1- 
> 
BELAJEFF, W.: Ueber die Reductionstheilung des Pflanzenkernes. (Vor- 
laufige Mittheilung.) Ber. d. deutsch. bot. Gesells. 16:27-24. 18098. 
3. ———: Ueber die Centrosome in den spermatogenen Zellen. Ber. d. 
deutsch. bot. Gesells. 17 : 199-205. 1899. 
4. BLopGetTtT, F. H.: Vegetative reproduction and multiplication in Ery- 
thronium. Bull. Torr. Bot. Club 27 : 305-315. 1900 
. CALDWELL, O. W.: On the life-history of Lemna minor. Bot. Gaz. 
27: 37-66. 1899. 
. CALKINS, G. N.: Chromatin-reduction and tetrad-formation in pterido- 
hytes. Bull. Torr. Bot. Club 24: 101-115. 18 
. CAMPBELL, D. H.: A morphological study of Naias and Zannichellia. 
roc. Cal. Acad. of Sci. Bot. HI. 1: 1-61. 1897 
. CHAMBERLAIN, C, J.: (Contribution to the life-history of Lz/iwm Phila- 
elphicum.) The pollen grain. Bot. Gaz. 23: 423-430. 1897. 
. CouLTeR, J. M.: Contribution to the life-history of Lz/zum Philadel- 
on 
oO 
“I 
oo 
9 
phicum,; the embryo sac and associated structures. Bot. Gaz. 
23: 412-422. re 
0, oe to the life-history of Ranunculus. Bot. Gaz. 25 :73— 
88, 
: ee, B. M.: Studies in the development of the pollen grain in Sym- 
plocarpus foetidus and Peltandra undulata. Bot. Gaz. 29:8! 98. 
1900. 
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