10. EQUISETACEM. [1. Equisetum. 



very numerous. Pedicels usually paired, sometimes more numerous^ 

 quite free from the petiole and nearly so from one another. 

 In wet places throughout the province. Fr. Nov.-Jan. 



The following extreme forms occur, connected by many inter- 

 mediates : 



Var. a. minuta proper. Syn. M. erosa, Willd. 



A very small form with leaflets sometimes only •12--2" long and broad or up ta 

 •35", cimeately obovate on petioles 1-2" long, margin irregularly coarsely toothed 

 or lobulate. Capsules usually very numerous, several or in the same plant rarely 

 solitary at the base of each petiole, pedicels half as long again to twice as long as 

 the capsule, ascending. Capsule usually margined, sometimes also ribbed, upper 

 tooth longer. 



Common, Singbhum and other districts of Chota Nagpur ! 



Var. /3. major. Syn. M. quadrifoliata {Beng. PL non L.). 



A very robust form, leaflets 1" long and broad, entire, on petioles 6-10" long. 

 Sporocarps usually paired at the base of the petioles and often absent, sometimes 

 solitary •12-' 18" long, rarely margined, not ribbed. Pedicels mostly decm-ved 

 and ascending, •2", long. 



Also common, usually in running water ! 



This closely resembles the African M. diffusa, Lepr. ! Should the pedicels be 

 shorter than the capsules and the latter be fiunished with erect instead of strigose 

 hairs, it would be -1/. gracilenta, A. Br. 



EQUISETALES. 



FAM. 10. EQUISETACEiE. 



Stem symmetrical erect or scrambling from a perennial creeping 

 rootstock, jointed, sulcate, hollow except at the septa and with air 

 canals beneath the grooves. Leaves reduced to the teeth of a foliar 

 sheath arising from one internode and embracing the next, the teeth 

 corresponding with the ridges. Branches or whorled, springing 

 from inside the base of the foliar-sheath and alternating with the 

 teeth. Sporangia 5-10 on the under-surface of the sporophylls, which 

 correspond in position and origin to the leaves and become modified 

 into the peltate scales of a terminal cone, either on the summit of 

 ordinary or of special cone-bearing stems. Sporangia opening by a 

 slit towards the stalk of the sporophyll. Spores of one kind, developed 

 from a hypodermal archesporium as in the ferns, with several coats 

 which split into spiral hygroscopic bands (elaters), the function of 

 which appears to be to keep groups of spores (which develop function- 

 ally one-sexual prothalla) together. Prothallium well-developed, 

 fiat and pluricellular. 



1. EQUISETUM, L. Horse-tail. 



Characters of the family. Only one genus. 



ycrambUng or subscandent. Branches sparse, weak. Cones sub- 

 sessile, rounded or apiciUate ....... 1. debile. 



Erect. Branches dense. Cones shortly peduncled, obtuse . .2. diffusum. 



1. E. debile, Roxb. 



Stems lax scrambling and often attaining 10 ft. among bushes. 

 Branches long slender few, often only 2-3 in a whorl. Internodes 



78 1219 



