X] ANNULAKIA. 341 



Annularia sphenophylloides (Zenk.). Fig. 89. 



1833. Galium sphenophylloides, Zenker^. 



1865. Annularia hrevifolia, Heer'', Strobilus. 



1876. Calainostachys {Stachannularia) calathifera, Weiss^. 



Principal branches 8 — 12 mm. wide, with internodes 8 — 10 

 cm. in length, giving off two opposite branches at the nodes ; 

 from the secondary branches arise smaller branches in opposite 

 pairs. The leaf-verticils and branches are all in one plane. 

 Each verticil consists of 12 — 18 spathulate segments, 3 — 10 mm. 

 long, cuneiform at the base and broader above, with an acuminate 

 tip ; the lateral segments are slightly longer than the upper 

 and lower members of a whorl. 



The small and crowded leaf-whorls give to this species a 

 characteristic appearance, which readily distinguishes it from 

 the larger-leaved forms such as Annularia stellata. A fossil 

 figured by Lhwyd^ in 1699 as Rubeola mineralis is no doubt an 

 example of Annularia sphenophylloides. 



Annularian branches are occasionally found with cones given 

 off from the axils of some of the leaf-whorls. An interesting 

 specimen, which is now in the Leipzig Museum, was described 

 by Sterzel in 1882^ showing cones attached to a vegetative 

 shoot of Annularia sphenophylloides. The long and narrow 

 strobili — 2"5 cm. long and about 6 mm. broad— appear very 

 large in proportion to the size of the vegetative branches. A 

 fertile shoot consists of a central axis bearing whorls of bracts 

 alternating with sporangiophores, to each of which are attached 

 four sporangia. The specimen in fig. 89, A, does not show the 

 details clearly; each transverse constriction represents the 

 attachment of a whorl of linear bracts ; the whole cone appears 

 to consist of a series of short broad segments. The divisions 

 in the lower half of each segment mark the position of the 

 sterile bracts, while those of the upper half represent the out- 



1 Zenker (33), PI. v. pp. 6—9. 



^ Heer (65), fig. 6, p. 9, and other authors. 



3 Weiss (76), p. 27, PI. in. fig. 2. * Lhwyd (1699), PI. v. fig. 202. 



6 Sterzel (82). 



