Class XXI.— CEYPTOGAMrA. 



308. EQUISETUM.. L. (Horse-tail, Shave^ 



grass-.) 



Floral receptacles peltate, many angled, col-- 

 lected into a spike. Indusium coniiculate. Sta- 

 mina. 4. Style none. Seed 1. 



Herbaceous and leafless plants with fistulous striated 

 stems which are either simple of branched, ramuli most= 

 \y verticiUated, — articulated, joints surrounded with den- 

 tated sheathes. The vernal flowering stems, for the most 

 part, quickly perishing are succeeded by others which 

 are barren and more durable. 



Species. 1. E. arvense. 2. sylvaticum. 3. uliginosnm. 

 4. pahistre' 5. scirpoides. 6. A?/ema/e. (Shave-grass). Ve- 

 ry abundant on the banks of the Missouri below the 

 Platte, and called '* Rushes;" it is found to be injurious 

 to horses wiiich feed upon it for any considerable 

 length of time. 



A genus principally indigenous to Europe. 



BO^. LYCOPODIUM. L, (Club-moss.) 



Capsules reniform, 1 -celled, 2-valved, many^ 

 seeded. Seeds very minute, resembling powder,. 



Herbaceous and branched, repent or erect; leaves- 

 imbricated and often spreading ordistichal, sempervirent; 

 spikes simple or dichotomous, sessile or pedunculatCj . 

 terminal or axillary. Seed inflammable. 



Species. 1. L. carolinianiim. 2. clavaium. 3. trista- 

 ekyum. Ph. Neai-ly allied to the preceding, but with the 

 leaves entire, and not serrate as in No. 2. 4. complanw 

 izim. 5. sabincefoliiim. 6. dendroideiim. (Ground Pine) 7o 

 annotinum. 8. inundatum. 9, alopeciiroides. 10. sclagi- 

 fioides. 11. rvpestre. 12- albidulinn. A mere variety of 

 'Jie following? 13. apodum. 14-. lucididum. 



