KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 25. N:0 2. 143 



The latter half of this diagnosis was probably based 011 specimens of C. ramosus; 

 at all events it is to that species that all the specimens used by Angelin to illustrate the 

 arm-structure of C. lortgimanus must be referred. The name »longimanus», moreover, 

 alludes, one can hardly doubt, to the long, straight appearance of the arm-branches in 

 those same specimens. Not only are some specimens described as belonging to this spe- 

 cies to be referred to C. ramosus, but one of the two figured specimens of C. ramosus 

 belongs almost certainly to C. longimanus. It would, therefore, have been more eon- 

 venient to have followed the dictates of coinmon sense and to have given the name longi- 

 manus to that species containing the greater number of specimens to which it was appro- 

 priate and to which it would have undoubtedly been applied by Angelin. This course, 

 however, would have ignored the three specimens figured as C. longimanus on Tab. XX, 

 which have the first claim to be considered as type-specimens of the species. We are 

 therefore bound by the letter of the laws of nomenclature to use the names in the sense 

 heiv ascribed to them for the first time; I say »for the first tirne» since we are also driven 

 to admit that the author of these species did not understand what were the characters by 

 which they were really separated. 



The following description is based on the following specimens, all in the Riks- 

 museum: (a) No. 137, a crowu without stem, the original of Tab. XX, fig. 4; (b) No. 142, 

 a ventral sac and adjacent structures, the original of Tab. XX, fig. 7; (c) No. 137, label- 

 led C. longimanus by Angelin but not figured, a very large, conical specimen; (rf) a nice 

 little crown with short stem, very like Tab. XX, fig. 4; (e) No. 156, an old individual 

 with ornament tending to C. zonatus; (f) No. 499, a battered crown, doubtful; (g) No. 

 161, a small crown, rather doubtful; (Ii) No. 153, a very small cup, 6 mm. high, rather 

 doubtful; (i) No. 178, a large crown with a little of the cup löst. There are also nume- 

 rous other arm-fragments sorne of which probably belong to this species, but I cannot 

 undertake the minute examination that would be required to determine all of them. 



Description. 



Dorsal Cup conical, with the sides at an angle of 15 — 20° to the vertical and 

 slightly curved convexly. The height of the cup is about 8 / 4 its width, or sometimes 

 almost equal to the width. 



IBB 5; pentagonal. They stånd ont a little from the column, but are not very 

 protuberant. Height 6.75 mm.; width below 6 mm.; width above 7. G mm. 



BB 5; hexagonal, except post. B which is heptagonal. The surface is almost plane, 

 but the sutures are a little sunk. Height 10 mm.; width 9.5 mm., sides almost parabel. 



RR 5; pentagonal or shield-shaped; rather more swollen and rounded than IBB and 

 BB; bent inwards above. The articular facet occupies half the width. Height 11.2 mm.; 

 height to bottom of facet 7 mm.; width below 11.5 mm.; greatest width 13 mm.; width 

 of facet 6 mm. The axial canal is distinct and rather towards the outer side of the facet. 



The Arms dichotomise regularlv tive times or more; they lessen in thickness quite 

 gradually, and never get very firie. They have not that very straight appearance so 

 characteristic of C. ramosus, but are gently curved in the interaxillary portions. The 

 arm-ossicles are rounded, but not exactly moniliform, and in section are rather wider than 



