10 SYDNEY J. HIOKSON. 



Winter Quarters locality is 220 mm. The diameter of the colony is in all specimens 

 about 30 mm. 



The calices are about 1 ' 5 mm. in height. They are clustered together at the 

 ends, but scattered at considerable intervals near the base of the branches. There 

 are a few calices on the main axis itself. The spicules are overlapping scales, oval 

 or heart-shaped on the general coenenchym and on the base of the calices. 

 Diameters of these scales, taken at right angles, are about • 43 mm. x • 4 mm. 

 The scales forming the operculum of the calyx have a thick, keeled spine, the 

 sharp, saw-like keel being on the oval side of the scale and extending from the 

 tip of the spine to the centre of the plate (fig. 19). The length of the spine is 

 about 0'4 mm., and the distance from the tip of the spine to the opposite border 

 of the plate • 64 mm. The breadth of the plate is • 43 mm. 



The type of this species was found by Captain Thouars off the Falkland Islands. 

 The species was also obtained by the ' Challenger' near the Crozets in 550 fathoms. 

 A good account of the genus and of the species belonging to it is given by Dr. Versluys 

 (13). The species was only figured by Valenciennes (12), but was subsequently 

 described by Professors Wright and Studer (14) from specimens obtained by the 

 ' Challenger.' 



I have compared the specimens with an example of Thouarella hrucii, kindly lent 

 to me by Prof. J. A. Thomson, and I am able to confirm the distinction of the species. 

 The scales are larger in T. antarctica, and the spines of the coronal scales longer and 

 sharper than in T. brucei. 



Primnoella divergens. 



E. end of Barrier, January 29, 1902. 100 fathoms. 



(Plate I., figs. 8, 9 & 10.) 



The single specimen of this extremely interesting species is 135 mm. in height, 

 but the base of attachment is lost, and the thickest part of the horny axis is 

 2 mm. in diameter. In the first notes I made I placed it in the genus Primnoella, 

 but on reconsideration and further study I transferred it to the genus Caligorgia, and 

 gave it the name C. squamata. Taking advantage of a visit to my laboratory by 

 Dr. Versluys of Amsterdam, whose great work on the Primnoidse of the Siboga 

 expedition (13) has just appeared, I asked him to examine the specimen, with the 

 result that it is returned to the genus Primnoella with the name P. divergens. 

 This hesitancy in determining the generic position of the specimen was due to the 

 fact that it occupies a position in the system almost exactly intermediate between 

 these two genera. It is either a very divergent Primnoella, or else a very divergent 

 Caligorgia. It is perhaps a matter of opinion whether it is most nearly related to 

 the former or to the latter genus. Dr. Versluys pointed out certain characters which 

 I had overlooked, and converted me to the view that it should be placed in the 

 genus Primnoella ; but it exhibits so many characters of Caligorgia, which I shall relate 



