A MONOGRAPH OF THE EXISTING CRINOIDS 207 



Fifteen of the specimens in the Boston Society of Natural History show the follow- 

 ing features : 



1. All the IIBr series are 4(3+4). The three remaining IIIBr series are 2. 



2. There are 34 arms 97 mm. long. The cirri have 27-30 segments and are 23 

 mm. long. The IIBr series are all 4(3+4). On the various postradial series the 

 IIIBr series are as follows: 0, 2, 4(3+4), 4(3+4); 0, 2, 2, 4(3+4); 0, 2, 2, 0; 4(3+4) 

 2,2,4(3+4)10,2, 2,0. 



3. There are 31 arms 97 mm. long. The cirri are XV, 32, 37 mm. long. All the 

 inner IIIBr series are developed, and all are 2; there is a single exterior IIIBr 4(3+4) 

 series. 



4. The cirri have 30 segments. All the IIBr series are 4(3+4). The five 

 remaining IIIBr series are 2. There is a single IVBr 2 series. 



5. All the IIBr series are 4(3+4). On three postradial series the IIIBr series 

 are 0, 2, 2, 0, and on the other two they are 0, 2, 2, 4(3+4). 



6. The arms are 122 mm. long, and the cirri have 30 segments. All the IIBr 

 series are 4(3+4). On three postradial series the IIIBr series are 0, 2, 2, 0, and on 

 the other two they are 4(3+4), 2, 2, and 0, 4(3+4), 4(3+4), 4(3+4). 



7. The cirri have 30-33 segments. The IIBr series are all 4 (3+4). On three 

 of the postradial series the IIIBr series are 0, 2, 2, 0, and on another they are 4 (3+4), 

 2, 2, 0. There is a single IVBr 4 (3+4) series present. 



8. There are 28-30 cirrus segments. The IIBr series on the left anterior and 

 left posterior postradial series are 2, all the others being 4 (3+4). On the left anterior 

 postradial series there are no IIIBr series; on the left posterior postradial series the 

 IIIBr series are 4 (3+4), 0, 0, 0; on the three remaining postradial series the IIIBr 

 series are 4 (3+4), 0, 2, 0; 0, 4 (3+4), 2, 0; and 2, 0, 0, 2. 



9. There are 31 cirrus segments. All the IIBr series are 4 (3+4). On the 

 several postradial series the IIIBr series are: 4 (3+4), 2, 4 (3+4), 0; 0, 2, 2, 4 (3+4); 

 4 (3+4), 2, 2, 0; 0, 2, 2, 0; and 4 (3+4), 2, 2, 4 (3+4). There are two IVBr 4 (3+4) 

 series. 



10. In a small broken specimen all the IIBr series are 4 (3+4). All the IIIBr 

 series, which are present on the remaining postradial series only internally, are 2. 

 The IVBr series are 4 (3+4). 



11. The IIBr series are all 4 (3+4). There is only one complete postradial 

 series on which the IIIBr series are 4 (3+4), 2, 2, 4 (3+4). Two other postradial 

 series have IIIBr 2 series remaining. 



12. There are 28-30 cirrus segments. Ah 1 the IIBr series are 4 (3+4). On two 

 postradial series the IIIBr series are 0, 2, 2, 0, and on two others they are 0, 2, 2, 4 

 (3+4); on the fifth they are 0, 2, 2, 4 (3+4) with, on the second, an inner IVBr 

 4 (3+4) series. 



13. There are 30 cirrus segments, of which the outer bear dorsal spines which are 

 rather more prominent than usual. One of the IIBr series is 2, the other nine being 

 4 (3+4). On two postradial series the IIIBr series are 0, 2, 2, 0; on the other three 

 they are 0, 0, 0, 0; 0, 0, 2, 0; and 2, 2, 2, 0. 



14. The arms are 124 mm. long. The IIBr series are all 4 (3+4). On two 

 postradial series the IIIBr series are all 4 (3+4); on two more they are 0, 2, 2, 0; 

 and on the fifth they are 4 (3+4), 2, 2, 0. 



