574 Mr. Henverson on the Reproductive Organs of Equisetum. 
Fig. 12. Spore, with the integument separated into filaments, detached before 
maturity, to show the latter partially unrolled. 
Fig. 13. Spore and outer tunic, after immersion in dilute tincture of iodine. 
Fig. 14. Highly magnified portion of the theca; a. line of dehiscence; 
b. meshes in irregular rows or areolz, in which spiral vessels are 
formed; c. muriform meshes, on which the vessels near the line of 
dehiscence incline to annular. 
Figures 3, 5, 9, 10, 11, 12, 13 & 14, are magnified 400 diameters. 
