CASH : FOSSIL FRUCTIFICATIO^'S OF YORKSHIRE COAL MEASURES. 445 
Binneyana upon the top of a Calamite, would be as abnormal as to 
surmount the stem of an Eqidsetum with the strobilus of a Lycopod." 
Weiss in his " Steinkohlen Calamarieu, Berlin, 1876," defines 
Calamostachys : " With paniculated shorter fruit spikes, mostly with 
separate tracts between which are the fertile whorls, consisting usually 
of six column-shaped bearers, each with four sporanzia ; each 
sporangium is attached to a disc-shaped enlargement (shield recep- 
taculum) of the bearer ; axis of the spike solid." 
He classifies the fruit spikes of his group Calaniarioe in three 
sections as follows : — 
1. The fruit spikes consist of fertile whorls without sterile 
ones — Equisetum. 
2. The fruit spikes with whorls of sterile strongly crossed foliar- 
discs (Deckblattkreise), the covers always on the upper end of the 
internodes and the fertile whorls arranged alternately ; for example, 
the small columns or bearers are : 
(a) Exactly in the middle betwen two sterile whorls, or in 
the greater distance from each of the two next whorls 
in Calamostachys^ Stachannidaria^ Macrostachya. 
(b) At the base of the internodes or in the angle of the discs 
upper leaf covers (Deckblattwinkle) in Paloeostachya 
(c) Discs at the upper end of the internodes under the leaf 
cover whorls (Deckblattwirtel) in Cingularia Huttonia. 
3. Finally (questionable), the sporangia are sessile in the angle 
of the upper leaf cover, in Volkmannia, 
R. Zeiller (vegetaux Fossiles du Terrain Houiller de la France, 
1880), refers Calamostachys to the A/uiularioe, under the name of 
Bruckmannia ^ as is evident from his description, " dans ceux de ces 
^pis (Bruckmannia), dont on a pu etudier la structure, on a reconnu 
des sporangiophores disposes par verticilles alternant avec des verticilles 
de hractees sferiles." 
Professor Renault includes Calamostachys among the EquisetaceJB 
(Cours de Botanique Fossile (Deuxieme Annee, Paris, 1882), under 
the genus Bruckmannia as fructification of Annularia, " incertaa 
sedis," and consequently among his Heterosporous Equisetacese, in a 
later publication of his (Sur les fructifications des Calamodendro7\s), 
