KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 25. N:<> 2. 141 



the species of Group III; the alternate ones project. In the type-speciraen the jurictioin 

 of the stem with the cup is trilobate, the anterior and left anterior IBB forming one lobe, 

 and the other three IBB being pretty evenly distributed between the other two lobes; 

 the left posterior IB is if anything larger than the rest. 



Angelin's figures are fairly correet, though cluinsily drawn. 



Locality, Follingbo (f). Xot known out of Gotland. 



Cyathocrinus distensus. 



(Plate VII, figs. 230—233.) 

 1878 Angelin, Iconographia, p. 23, Tab. III, tigs. 6, 6 a. 

 Diagnosis. 



Dorsal cup greatly expanded in region of RR. Articular facet of RR vertical, so 

 that arms spread out at an angle of between 4° and 10° with the horizontal. Facet 

 occupies nearly half width of R. Arms suddenly curve upwards on IIBr 2 , and diehoto- 

 mise to VIIBr; ossicles low and wide. 



Angelin's diagnosis of this species is longer than most. It is practically the de- 

 scription of the single type-specimen, and as such it is in the main correet. There appears, 

 however, from the evidence of Angelins MS. figures, to have been some eonfusion between 

 this species, which is undoubtedly a Cyathocrinus, and the somewhat similar form called 

 by Angelin Taxotrinus distensus; and this may account for some incorrect expressions in 

 Angelin 's diagnosis. This fact certainly accounts for the wrong locality given, since it 

 is Taxocrinus distensus that comes from Djupvik (bed c); the present specimen, however, 

 is undoubtedly not from that locality, as Professor Lindström assures me. 



The specimen has been much weathered and presents the appearance of having been 

 injudiciously cleaned with a sharp instrument. 



Description of the Specimen. 



Dorsal Cup rises from the stem in a steep cone but expands greatly in the region 

 of the radials. The measurements are: vertical height 6.5 mm.; width at base 4 mm.; 

 width at top of basals 5 mm.; width above, from radius to interradius, 10 mm. It is 

 thus seen that the base is by no means »subdilate» as in Taxocrinus distensus; nor can 

 the cup itself be correctl}- described as »sub-patelliform». 



IBB 5 ; pentagonal. As they are broken off in the specimen their exact height can- 

 not be ascertained; but since they appear to enclose a portion of a stem-ossiele it is im- 

 probable that they were much higher. They may therefore be described as low. 



BB 5; hexagonal, about as high as wide. Post. B appears to have been heptagonal 

 as usual, but its upper margin is barely decipherable. 



RR 5; swollen along the median radial line, but depressed in the interradial regions 

 where the processes ascend rather high. The facet occupies nearly half the width of the 



