X] ANNULARIA. 341 



Annularia sphenophylloides (Zenk.). Fig. 89. 



1833. Galium sphenophylloides, Zenker i. 



1865. Annularia hrevifolia, Heer^, Strobilus. 



1876. Calamostachys {Stachannularia) calathifera, Weiss 3. 



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 

 altei:nating 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. m. fig. 2. ■» Lhwyd (1699), PI. v. fig. 203. 



« Sterzel (82). 



