ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 693 



Polyspermy in Ferns.* — W. L. Woodburn describes and figures a 

 remarkable instance of polyspermy in Onodea struthiopteris, some pro- 

 thallia of which were supplied to him whicli had been preserved ten 

 hours after the introduction of spermatozoids. In one egg-cell no less 

 than seven spermatozoids were counted, entirely within the nuclear 

 membrane and occupying the central part of the nucleus. Nothing in 

 the appearance of the egg, either in the cytoplasm or nucleus, indicated 

 an abnormal condition of the egg or the egg-nucleus. The chromatin 

 network was broken up and irregularly massed, but it could hardly have 

 been otherwise after the entrance of so many spermatozoids. Besides 

 the seven spermatozoids which entered the egg-shell there were three 

 others lying in the concavity just above it. 



Studies on the Ophioglossacese.f — D. H. Campbell, during a recent 

 visit to Ceylon and Java, began to study the germination, development 

 and structure of the Ophioglossace^e, and, having secured and examined 

 much material, publishes his results, which, put briefly, are as follows. 



(I) The spores of 0. moliiccanum, when sown artificially, germinated 

 freely, but not beyond the stage of four cells, through absence of asso- 

 ciation with the mycorhizal fungus. The spores of 0. pendulum germi- 

 nated more slowly, and where associated with the fungus produced a 

 prothalhum of 12-13 cells. (2) Chlorophyll was found in 0. moluccamimy 

 but not in 0. jjendiduiu. (3) Adult natural prothallia of both these 

 species were found, and also of another species undetermined. (4) The 

 gametophyte is subterranean and normally lacks chlorophyll ; it is 

 radial in structure. It is short-lived in 0. moluccanum, but larger in 

 0. pendulum and capable of unlimitedlreproduction by means of detached 

 buds. (5) The antheridium agrees with the description given by Lang 

 and Bruchmann ; the spermatozoids are very large and in development 

 resemble those of Equisetum. (6) The archegonium resembles that of 

 Marattiacese ; two neck-canal cells may be present, and there is always 

 a division of the canal-cell nucleus. A ventral canal-cell was demon- 

 strated in 0. pendidum. (7) The basal wall of the embryo is probably 

 transverse in most cases, but varies in 0. pendulum. The foot, derived 

 from the whole hypobasal half of the young embryo, varies in degree of 

 development. (8) There are three types of the embryo. In that of 

 0. moluccanum leaf and root only are developed. In that of 0. vulgatum 

 root and stem, with a late development of the foliage-leaf. In 0. pen- 

 dulum roots only, (9) The definite sporophyte in both 0. moluccanum 

 and 0. pendulum is formed as an adventitious bud upon the root of the 

 embryo sporophyte. (10) In 0. moluccanum the tissues of cotyledon 

 and primary root are continuous, and the structure of the axial vascular 

 bundle is essentially the same throughout — collateral in leaf, monarch 

 in root. The primary root of 0. pendulum is diarch like the later roots. 



(II) The type of embryo in 0. moluccanum is primitive and has its 

 nearest analogy in Marattiaceas and Equisetum, its growth being bipolar 

 and itself perforating the gametophyte. (12) The nearest affinity of 

 Ophioglossum is probably with Marattiaceae, but probably a more remote 



* Bot. Gazette, xliv. (1907) p. 227 (1 fig.). 

 ' t Ann. Jard. Bot. Buitenzorg., xxi. (1907) pp. 138-94 (11 pis.). 



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