"endeavour" scientific results. 176 



Mesial sarcotheca tubular, about as long as the hydrotheca,. 

 straight or slightly curved, free for one-fourth or one-third of 

 its length and often diverging somewhat from the hydrotheca, 

 the circular terminal aperture often united to the inferior one. 

 Lateral sarcotheca? tubular, nearly erect, closely adnate to the 

 hydrotheca throughout and reaching more than three-fourths the 

 height ,of the latter, apertures as in the mesial. Cauline 

 sarcotheca?, two in front close to the base of each hydrocladium 

 (the upper larger), and one at the back. A crateriform elevation 

 with a circular aperture on each hydrocladinm-process. 



Gonangial branch replacing a hydrocladium — female, com- 

 mencing with about eight to ten internodes bearing modified 

 hydrotheca?, often deformed and united by perisarcal growths ; 

 corbula closed, consisting of about fourteen or fifteen pairs of 

 alternate leaflets, each bearing on the distal side at the base a 

 projecting sarcotheca and above it a minute irregular 

 hydrotheca (?) with two or three sarcotheca? above ; distal 

 edges of the leaflets higher up continued into extremely large 

 foliaceous expansions which project outwards on all sides, 

 dividing into several very large lobes, all profusely fringed with 

 sarcotheca?: male, commencing with about four hydrotheca 1 , not 

 much modified, corbula differing from the female in the much 

 smaller foliaceous appendages. Small apertures at the bases of 

 the leaflets covered by the rudimentary hydrotheca?. 



Colour. — Light brown. 



This is a handsome plumose species, with closely-set hydro- 

 cladia, which are about one-third of an inch in length. Its 

 branches are directed forward from the stem, springing from the 

 front, and not taking the place of a hydrocladium. The long 

 tubular hydrotheca? are very distinct from those of any other 

 species known to me, and the peculiar position of the intrathecal 

 ridge is a character shared only by A. megalocarpa. There is 

 some variation in the angle at which the hydrotheca? are borne, 

 especially marked in those on the proximal portion of the 

 gonocladium, which are much less erect than the others. The 

 marginal teeth are distinct; typically the first on each side is 

 triangular and acute, while the second is more broadly rounded, 

 but exceptions are common. The mesial sarcotheca may be quite 

 straight, or a little incurved towards the hydrotheca, or with the 

 free portion somewhat directed away from it. 



The gonangial structures are very remarkable. The male and 

 female colonies differ not only in the corbula itself, but in the 

 arrangement of the proximal internodes of the gonocladium, 

 those of the male bearing only four or live hydrotheca?, which are 

 normal or nearly so, while in the female there are eight or ten, 

 many of which are, in the specimens examined, more or less 



