394 
VASCULAR CRYPTOGAMS. 
prothallia are larger (as much as ^ inch) ; Hofmeister compares them to the thallus 
of Anthoceros pundatus, Duval-Jouve to a curled endive-leaf. Duval-Jouve states 
that the antheridia appear about five weeks after germination, the archegonia much 
later. These statements refer especially to JE. arvense, limosum, and palustre ; 
according to the same writer, the prothallia of Telmaieia and sylvaticuvi are 
broader and less branched; those of E. ramosissimum and variegatum slenderer 
and more elongated. 
The Aniheridia^ arise at the end or margin of the larger lobes of the male 
Fig. 276.— Lobe of a highly developed female prothallium oi Eqiiisettim arvense cut through vertically (after Hofmeister, 
X about 60); a aa two abortive and one fertilised archegonium, h root-hairs. 
prothallium. The apical cells of the enveloping layer of the antheridium contain 
but little or no chlorophyll; they separate from one another on the addition of 
water (like those of Hepaticae), to allow the escape of the antherozoids, which are 
still enclosed in vesicles and number from 100 to 150. The hindermost and 
thickest of the two or three coils of the antherozoid, which is larger in this class 
than in all other Cryptogams, bears an appendage on the inner side which 
^ [Sadebeck, Ueb. die Antheridien-Entwickelimg der Schachtelhalme Sitzber. d. Gesellsch. 
natiufor. Freunde zu Berlin, 1875.] . 
