40 ' "ENDEAVOUR " SCIENTIFIC RESULTS. 



the hydrocladium half way through the hydrotheca, having its 

 free edge thickened and giving origin to a faintly indicated fold 

 which crosses the upper part of the hydrotheca towards the 

 anterior tooth ; distal part of the hydrotheca set at an angle of 

 about 40° to the internode ; border with a median anterior 

 tooth, which is bifid, the smaller point somewhat incurved, the 

 larger forming an acute crest above it; two huge teeth on each 

 side, and a third narrow pointed one at the junction with the 

 lateral sarcotheca ; back entire, adnate. Hydrothecal internode 

 with two very short, septal ridges (often scarcely indicated), one 

 opposite the proximal extremity of the hydrotheca, the other 

 about the middle of the internode. 



Mesial sarcotheca? about half the length of the hydrothecae, 

 adnate throughout, terminal and lateral apertures confluent, 

 forming an oblique canaliculate aperture. Lateral sarcothecae 

 sub-tubular, sharply recurved, completely open in front, margin 

 on a level with that of the hydrotheca or slightly projecting. 

 Cauline sarcothecae broader than laterals, completely open above, 

 two on the rachis at the base of each hydrocladium and a third 

 at the back of each axil. A crateriform prominence on each 

 hydrocladium-process. 



Gonangial pinnae with the first three or four internodes bear- 

 ing nearly normal hydrothecae, generally followed by one or two 

 bearing more modified hydrothecae (mostly without mesial 

 sarcothecae i. Corbula very long (sometimes over 18 mm.), 

 curved, consisting of up to nearly forty pairs of broad leaflets, 

 which unite to form a closed corbula, the junction-lines smooth, 

 marked by slig'htly thickened ridges. Basal part of each leaflet 

 with a row of sarcothecae along the lower and distal margins, 

 just above which is an opening filled by a small modified 

 hydrotheca A very large broad rouuded secondary leaf rising 

 from the upper part of each corbula-leaf, free except at the base, 

 directed obliquely forward and fringed with sarcothecae. A row 

 of sarcothecae usually running up each leaf of the corbula proper, 

 Starting from the point where the secondai'y leaflet originates. 



Colour. — Red-brown. 



This fine species is unique in several of its characters, notably 

 in the form of the hydrothecae and the direction of the intrathecal 

 ridge, and in the enormous corbula;. In its height (fully two 

 feet), it vies with the last species, but is a slender foim, with 

 comparatively few branches. In the larger of the two colonies 

 examined a spongy root-mass, some two inches in diameter, gives 

 origin to half a dozen distinct stems, averaging about k 2 mm. in 

 diameter, of which three attain the maximum height. The 



