48 



low and gradually increase in height distalwards. In region 2 the ossicles are consider- 

 ably higher. In region 3 the ossicles are 1 mm. liigh and are higher than in any other 

 part of the stem. In region 4 the ossicles increase in both transverse and sagittal dia- 

 meter. The ossicles in regions 4, 5 and 6 are very regular in size whether cirriferons or 

 not, thns markedly differring from //. Ammonis; their general height is between 7 mm. 

 and 1 mm. In the strongly curved portions of the stem, both involnte and evolute, the 

 height of the ossicles is greater on the greater curve; in specimen '/ an ossicle that mea- 

 snres 1 mm. in outside height has an inside height of 0,63 mm., or ~ ... 



The coil of the stem is rather loose and like a bishop's pastoral staff. 



The cirri spring from the angles of the ossicles, on either side of the inner con- 

 cavity. They are slender, and composed of moniliform ossicles. In the proximal part of 

 each cirrus the ossicles have a diameter of about 1 mm. and a height of 0,75 mm. The 

 cirri are longest in region (!, where they may attain a length of 1(5 mm. 



The outer latcral sutures are plainly seen. They are about half-way between the 

 median outer line and the origin of the cirri. They ean be traced from the distal erod of 

 the stem, where they are most distinct, up to the distal end of region 1. No otliei' 

 sutures are visiblc 



Notes on Angelin's figures: 



Tab. X, tig. 24. The armlets are drawn as dichotomising, but there is no evidence 

 for this. The numbers of the arm-ossicles are wrong. The ontline of r. post. R\ and 

 the lower part of the ventral tube are wrong. A slightly better drawing of the crown 

 occurs in Angelin's MS., p. 174. 



Tab. X, fig. 25 is very slightly enlarged. In the three distal centimetres the cirri 

 or their articulations should have been shown on each ossicle, and all ossicles should have 

 been of the same size. In the succeeding part more cirrns-ai-ticnlations occur than are 

 shown, and the ossicles bearing them are slightly swollen. 



Localities: Specimens a — h come from Follingbo (f); specimen / is from Burgen 

 in Endre (f). Specimen i comes from an opening neär the high road \\. of StjernarfVe 

 in the soke of Eksta (d); specimen j from Kyrkviken, Fårö (d); and specimens /, ///, n 

 from Söderholm and Norderholm, Fårö (d). 



Herpetocrinus convolutus, 



(Plate II, figs. 50 — 53.) 



1852. Myelodaetytvs convolutus, Hall, Nat. Hist. N. V., Palaeontology vol. 11. p. 192, Pl. XLII, 

 figs. 5 " — /' and (> a- Ii. 



Emended diagnosis. 



Cirri 2 to each ossicle; cirrns-ossiclcs mnch longer than wide, squarish in section. 

 Outer median and lateral sutures elear. Coil close. 



