63 
form a sort of envelope ; later on, however, they grow out in a straight 
_ line, and often again terminate in cystocarps. 
“No sharp lines of demarcation exist between the axes of different 
ranks ; they gradually change one into the other. Originally every 
_ they are short shoots ‘which terminate in a disc-shaped, lamellose cell- 
expansion composed of short branches lying close together. es, 
“The cystocarps, abundantly present, occupy a terminal position 
_ othe axes of the first rank. The favelli consist of a large specially 
formed complex of spores, at the base of which others afterwards 
- thoot out. Those figured in Plate XVIL., Figs. 2 and 3, are both very 
oun 
g. ; 
“The tetrasporangia (Plate XVI. Fig. 4) are subdivided into 
tetrahedra ; they are usually placed singly on the first joint cells of 
“The joints of the stoutest branches were as much as 400 p long, 
‘With a diameter of as much as 120. The joints of the thinner main 
_ ‘es were 100-200 » long, with a diameter of 20-50 p. In the branches 
_ higher rank the length and diameter of the cells of the joints then 
; ply decrease. The short cells, which produce branebes of the 
_ ‘strank, are 8-13 p long, with a diameter of 4-7 p. 
7 . rof. Schmitz, who had the kindness to send me some valuable 
 “Mmunications upon the subject of this species, as well as upon some 
ther alge from Adelaide, upon which I shall perhaps nes ti 
8 
ce. - spinescens, Kuetz. (Tab. Phye. XI., Plate 88), but I have 
. hitherto seen no authentic Risers of the latter, so that I hesitate to 
serine your alga at once as Call. spinescens, Kuetz. Then your 
8" 18 nearly related to Call. aculeatum, Harv., but is not, of wed 
identical with it; for example, the ecial formation of the 
Her Whorl-branchlets, as well as the appearance’ of the fs 
' Cat ication. Furthermore, your alga is in a slight degree relate Me 
ee Maller, Sond., which J. Agardh. now desires to elevate . ae 
q alg - f a different genus, Heterothamnion (see J. Agardh. ie 
4 a5) nce Ex. act. Soc. Lundensis, vol. 28, Lund., 1892, pp- / @ 
on Adelaide. 
(Plate XVI, Fig. 4; Plate XVIL, Figs. 2-3) 
