A MONOGRAPH OF THE EXISTING CRINOIDS 17 



Eudiocrinus loveni: IBr 2 -89; brachials 2-88; 4-85; 5-83; 6-74; 7-69; 

 8-60; 10-69; 11-64; 13-66. 



Amphimetra tessellata: Brachials 2-86; 4-92; 5-96; 6-100; 7-101; 8-95; 

 10-90; 11-87; 12-84; 13-83; 14-88; then (81-) 86-90. 



Ponliometra andersoni: Brachials 2-88; 4-91; 5-92; 6-94; 7-93; 8-93; 

 9-90; 10-89; 11-85; 12-78; 13-74; 14-80; distal brachials 80-90. 



Pectinometra flavopurpurea: Brachials 2-80; 4-80; 5-80; 6-78; 7-78; 8-76; 

 9-76; 10-71; 11-72; 12-73; 14-72. 



Asterometra anthus: Brachials (1 about 100); 2-84; 4-87; 5-92; 6-95; 

 7-87; 8-84; 9-77; 10-69; 12-71; 13-70. 



Diodontometra bocki: Brachials 2-83; 4-86; 5-87; 6-93; 7-96; 8-97; 9-93; 

 10-91; 11-90; 12-81; 13-78; 14-73; 15-75; 16-73. 



Clarkometra elegans: Brachials (1-103); 2-68; 4-87; 5-105; 6-106; 7-83; 

 8-60; 10-69; 11-65; 12-64; 13-62; 15-65; then about 64. 



Heliometra glacialis: Brachials 2-67; 4-87; 5-95; 6-105; 7-106; 8-108; 

 10-108; 11-96; 12-87; 13-75; 15-82; 16-70; 17-74; then about 70. 



Hypalometra dejecta: Brachials 2-78; 4-96; 5-100; 6-97; 7-86; 8-80; 

 10-62. 



Thaumatocrinus jungerseni: Brachials 2-98; 3-101; 5-93; 6-90; 7-86; 

 8-82; 9-77; 11-62; 12-63; 13-58; 14-63; 15-61; 17-60. 



Pentametrocrinus diomedeae: Brachials 2-98; 3-98; 5-88; 6-84; 7-80; 8-78; 

 10-60; 11-66; 12-53. In a larger specimen: Brachials 2-98; 3-96; 5-92; 6-88. 



Atelecrinus helgae: Brachials 2-64; 4-67; 5-72; 6-67. 



Metacrinus nobilis tennis: IBr 2 -82; IBr 3 -90; IIBr,-90; IIBr 2 -82; IIBr 4 -80; 

 IIBr 6 -88; IIBr 6 -84; IIIBr,-98; IIIBr 2 -91; IIIBr 4 -85; IIIBr 6 _ I2 -about 90; 

 IVBrj-102 ; IVBr 2 -99; IVBr 4 _ 10 -about 90; brachials 1-93; 2-98; 4 and following 

 about 90. 



Gisl6n said that from the preceding figures, which might have been supplemented 

 with others from about 40 additional specimens examined but not tabulated, all of 

 which point in the same direction, we learn the following: The first two brachials 

 following an axillary always have a relatively long outer and short inner side. The 

 distal articular line of these brachials therefore makes a relatively large angle with 

 the proximal. The arms, which following the arm division would diverge widely, 

 are thus brought closer together, which because of the limited space is of considerable 

 importance. In reality the length of the outer sides of these brachials is so much 

 greater than that of the inner sides that the distal articular line of the second brachial 

 slopes inward. 



In Metacrinus the proximal and distal margins of the brachials after the first or 

 second postaxillary are fairly parallel, but in the other types examined a more or less 

 pronounced obliqueness usually sets in sooner or later. In the first syzygial pair 

 (composed usually of brachials 3+4) this obliqueness is generally only slight the 

 greater length of the inner side in this pair has counterbalanced almost completely 

 the inward slope that was apparent on the distal margin of the second brachials. 

 The distal edge of the fourth brachial is therefore very often nearly at a right angle 

 to the longitudinal axis of the arm. Subsequently there usually follow a greater or 

 lesser number of brachials in which the proximal and distal edges show a tendency 



