152 MORPHOLOGY, ETC., VASC. PLANTS [Bot. Absts., Vol. IV, 



or very few branches; a relatively small number of female flowers produce fruit, which attain 

 nearly the normal size. — Proliferation. The female flowers of an inflorescence show foliar 

 proliferation; the male flowers seem to have been abnormal leaving only a few fragments on 

 the spadix.— Fruit without seed. The fruit has an ellipsoidal form, but is of the ordinary 

 length. — Fruit with two cells. Each cell has a normal seed. — Polyembryony. Occasionally 

 cocoanuts produce three or even four stems. It seems that in most of these cases the fruit is 

 one-celled and contains one seed. As only one of the germinating holes is pierced and the 

 young plants are wholly free from each other the phenomenon is to be ascribed to a form of 

 polyembryony. — J. J. Smith. 



990. Steil, W. X. Apospory in Pteris sulcata. Bot. Gaz. 67:469-4S2. 4 fig. 8 pi. June, 

 1919. — The embryo sporophyte of Pteris sulcata is of apogamous origin. The gametophyte 

 generation is ordinarily produced by the germination of a spore, but under certain conditions 

 w f as produced aposporously. Such gametophytes or gametophytic portions were formed in 

 connection with the lamina or the petiole of the primary leaf. In one instance a prothallium 

 was produced from both lamina and petiole. A sharp line of demarcation usually exists be- 

 tween the cells of the gametophyte and the sporophyte. The prothallial portions developed 

 antheridia, secondary prothallia, and in one instance a sporophyte-like outgrowth. The an- 

 therozoids, produced by the aposporously developed prothallia, were actively motile and nor- 

 mal in appearance. Occasionally forms intermediate in character between gametophyte and 

 sporophyte were formed. It is probable that the origin of the aposporously produced gameto- 

 phyte may be traced to an early stage in the development of the embryo. Since the embryo, 

 on account of its apogamous origin, is intimately connected with the prothallium, it is possible 

 that cells of the prothallium may be embodied in the developing embryo. These cells, retain- 

 ing the power to divide, may produce such outgrowths as have been described. — IF. N. Steil. 



991. Stevens, Neil E. The development of the endosperm in Vaccinium corymbosum. 

 Bull. Torrey Bot. Club 46 : 465-468. Fig. 1-4. 1919. — In Vaccinium corymbosum the develop- 

 ment of the endosperm may begin by a cross wall, following the first division of the primary 

 endosperm nucleus, as is the case for many other Ericaceae; or by a period of free nuclear 

 division. This one species, therefore, exhibits methods hitherto associated with different 

 groups. — P. A. Munz. 



992. W atkins, J. R. Pitch pockets and their relation to the inspection of airplane parts. 

 Jour. Franklin Inst. 188: 245-263. Fig. 1-3. 1919— See Bot. Absts. 4, Entry 480. 



993. Arbek, Agxes. Studies on intrafascicular cambium in monocotyledons (III. and IV). 

 Ann. Botany 33 : 459-465. Fig. 1-7. 1919. — The occurrence of a cambium is recorded for the 

 first time in members of the Juncaceae, Haemadoraceae, Amaryllidaceae, and Cyclantha- 

 ceae. A cambium has now been seen in nineteen families and in ten out of eleven cohorts of 

 monocotyledons. In the eleventh cohort (Triuridales) cases are here described of an arrange- 

 ment of the elements which may be interpreted as indicating cambial activity. — The structure 

 of the leaf bundles of Vcraintm album is described in some detail. In this species the cambium 

 which is well developed appears in the summer, persists through the winter and functions in 

 the succeeding year. There is a clear differentiation between the secondary xylem and the 

 primary metaxylem, a condition which has been observed in a number of other monocotyl- 

 edons. The xylem of the laterial veins is attached to the secondary xylem of the bundles from 

 which they arise. — W. P. Thompson. 



994. Bailey, I. \V. Depressed segments of oak stems. Bot. Gaz. 67: 438-441. 4 fig. 

 1010.— This paper is essentially a defense of the author's views against certain criticisms made 

 in a recent paper by Langdon (See Bot. Absts. 1, Entries 5S1, 1154). That the deeply de- 

 pressed segments of young oak stems are correlated wit h the presence of pairs of approximated 

 multiseriate rays rather than the Btellate arrangement of the primary elements is indicated 



only by a comparative study of tin- Btems of various arborescent dicotyledons, but also 

 1 numerous facts in the anatomy of mis Qucrcus. Exception is taken also to Lang- 



