403 
II. FLOWERLESS PLANTS. 
Sul)stance of the plant wholly of cellular tissue (except- 
ing in the Subclass Ductulosce which has a few ducts). 
No woody fibre. No true flowers with stamens and pistils. 
No distinct embryo or cotyledons. 
Class III. 
CRYPTOGAME^ DUCTULOS^. 
Plants with a few ducts amongst the cellular tissue, but, 
according to Arnott, no tracheae '. 
Order XCIII. EQUISETACEiE. 
Leafless branched plants v^^th a striated fistular stem, articu- 
lations sheathed at the base. Sj)orules siuroimded by elastic 
clavate filaments and inclosed in thecae arising from the peltate 
scales of terminal cones. — Vernation straight. Cuticle aboimding 
in silex. Only one genus. 
1 . Equisetum Linn. Horse-tail. 
* Fertile stems mostly unbranched and succulent ; barren ste?ns 
with whorled branches. 
1. E. arvense (L.); sterile st. with few furrows slightly sca- 
brous, branches rough with 3 or 4 simple angles, fertile st. simple 
with few lax distant sheaths. — E. B. 2020. N. 77- — Sterile st. 
numerous, procumbent or ascending, with numerous whorls of 
numerous roughish usually simple branches having 3- or 4-tooth- 
ed sheaths, each tooth long and acute with 1 rib extending to its 
* Those who desire to obtain an intimate acquaintance with the 
British Ductulosce are referred to Newman’s History of British Ferns, 
ed. 2. which is quoted (N.) in these pages. 
