48 " ENDEAVOUR " SCIENTIFIC RESULTS. 



of the primary corbula-leaves, arching over and overlapping those 

 in front of them. Similar structures, but much less regular and 

 symmetrical, occur in A. crucialis and other species, where they 

 are formed by a development of the free margins of the com- 

 ponent leaves ; here however, they originate independently, and 

 are not continual ions of the margins. The lines of union of the 

 corbula-leaves arc smooth, and not bordered by rows of 

 sarcothecee, but such a row usually runs up the leaflet from the 

 point at which the crest-leaflet starts. 



Loc. — Great Australian Bight, 40 to lUO fathoms. 



Aqlaophenia decumbens, sp. nov. 



(Plate iv., fig. 4; Plate vi., fig. 6.) 



Hydrophyton lax, slender, polysiphonic, about four or five 

 inches in height, sparingly branched ; branches springing from 

 the supplementary tubes, mostly in the distal poi'tions of the 

 colony, irregular, forming angles with the stem of about 45°. 

 Hydrocladia slender, alternate, one on each internode, both series 

 directed towards the front, and rising at an angle of about 40°, 

 nodes transverse. 



Hydrothecre long, parallel with the hydrocladium, a slight fold 

 or ridge near the base on the adcauline side, directed a little 

 forwards ; border with a median anterior tooth, bent outward, 

 and four nearly equal regular shallow triangular teeth on each 

 side, the last pair behind the lateral sarcotheca? ; back adnate. 

 Hydrothecal internodes with curved septal ridges opposite the 

 intrathecal fold and the base of the lateral sareothecae. 



Mesial sarcotheciE a little longer than the hydrothecoe, directed 

 very much forward, free part projecting beyond the hydrotheca- 

 margin, tubular, with distinct terminal and lateral apertixres, and 

 an aperture communicating with the interior of the sarcotheca. 

 Lateral s-arcothecffi subtubular, directed forward and outward, 

 rising about as high as the hydrotheca-margin ; terminal and 

 lateral apertures distinct or united. Cauline sareothecae large, 

 canaliculate, two on the rachis at the base of each hydrocladium. 



Gonosome — ? 



Colour. — Light brown, stem and branches darker. 



There is some doubt as to whether this species is identical with 

 the A. brevicairfit;, Kirchenpauer. That species is described as 

 having a very thick but short stem, from the summit of which 

 spring several long slender branches, but the figure conveys the 



