ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 71 



collected by Dr. Landman on the Regnell Expedition to South America. 

 His results serve to confirm or supplement those obtained by Karsten, 

 Johow, and others. The two species examined were Leiphamos azurea 

 and Voyria coerulea. He finds in the former a whorl of disc-like scales 

 at the base of the sepals, similar to that already described in other 

 species. In the anatomy of the roots, L. azurea approaches most nearly 

 L. tenella, which represents the most reduced type of the genus. In 

 fiis species, too, as Johow also found in the species which he studied, 

 the fungal hyphas which form a well-marked mycorhiza in the root, 

 occur also in the tissue of the stem penetrating to directly beneath the 

 flower. In contrast with Johow's statement as to the absence of stomata 

 from all leaf- and stem-organs in West Indian saprophytes, including 

 species of Leiphamos, the author describes and figures these organs on 

 the reduced leaves of L. azurea, and also of L. aphylla. 



In the case of Voyria coerulea an account is given of the stem- 

 structure. No vascular bundles are present in the much-reduced 

 scale-leaves, but stomata occur sparingly on the inner surface. In the 

 structure and development of the ovules, this species differs from 

 Leiphamos, in which Johow found the ovules erect and with no integu- 

 ment. Here also occurs the phenomenon noted by Johow, that many 

 ovules remain sterile, forming hair-structures like paraphyses. The 

 . ovules in V. coerulea are anatropous and have a single integument, thus 

 agreeing with those of other members of the order. 



As Leiphamos and Voyria show but little agreement in their ana- 

 tomical structure, and also differences in seed-structure, pollen, etc., it 

 is probable that the two genera are not so closely related as has some- 

 times been supposed. Leiphamos would seem to be a remarkably 

 reduced and isolated type, while Voyria shows more agreement with 

 the Gentianacese in general. 



Structure of the Extrafloral Nectaries of Hevea. * — Aug. Da- 

 guillon and H. Coupin describe the form and internal structure of 

 the glands which occur in different species of this genus of Euphor- 

 biaceae, at the top of the petiole on its upper face, near the origin of 

 the three large leaflets. These glands, although used by systematists in 

 the distinction of species, do not seem to have been studied anatomically. 

 In Hevea brasilkiisis the glands, which vary from two to five in number, 

 form a little wart, in the centre of which is a more or less circular 

 depression, surrounded by a sort of cushion. The authors describe in 

 detail the internal structure of the central depressed glandular area, the 

 cushion and the rest of the gland, and draw special attention to two 

 points : (1) the presence of a ring of sclerosed parenchymatous cells in 

 the interior of the cushion ; and (2) the distribution and termination 

 of the laticiferous cells in the parenchyma adjacent to the glandular 

 surface and right among the cells of the secreting epidermis. 



Reproductive. 



Germination of Davidia.f— W. B. Hemsley describes the structure 

 of the fruit and the germination of the seeds in this genus, which is a 



* Comptes Rendus, cxxxvii. (190:?) pp. 767-9. 



t Journ. Linn. Soc. xxxv. Bot. (190;?) pp. 556-9 (1 pi). 



