20 CALAMOCKINUS DIOMED.E. 



There seems to be considerable irregularity in the number of syzygies 

 in the forks from the main branch of the arms. In the first foik, in 

 one case, there were two syzygies in the second joint ; but generally the 

 syzygies of the first fork, whether it be to the right or left, were on the 

 second and third joints. 



In the arm on the left in Plate I. Fig. 1, the first branch is on the right, 

 like the one already described, but having an additional intercalated joint 

 with a s^'zygy, in place of the single joint carrying a pinnule on the right 

 arm of the same interradial. The second branch is missing. The third 

 branch, on the right, begins at the seventeenth joint. Its fourth joint has 

 a syzygy, next the thirteenth joint, then the nineteenth joint, the twenty- 

 sixth, and the thirty-eighth. There are sixty-eight joints in the arm ap- 

 parently perfect. The fourth branch is also on the right hand side. The 

 first, third, and ninth joints of the main branch between the third and 

 fourth forks have syzygies, and the tenth joint is the axillary of the 

 fourth fork. 



The fifth fork is on the left, and the main stem continues apparently 

 as the right hand branch ; it has syzygies at the thirteenth, nineteenth, 

 twenty-ninth, thirty-second, thirty-eighth, fifty-eighth, sixty-third, sixty- 

 seventh, seventy-first, and seventy-third joints ; and there seem to be 

 seventy-seven joints, the arm appearing perfect. The fifth left hand branch 

 is an imperfect branch, with probably from forty to forty-five articulations. 



The axillary of the first fork of the arm on the riglit (Plate I. Fig. 1) 

 is the eighth brachial. The first fork is on the left, but the branch is at 

 least one third longer than the corresponding branch of the adjacent arm. 

 It has syzygies at the second, fourth, ninth, thirty-third, fortieth, sixty- 

 seventh, seventy-sixth, and eightieth joints, and has eighty-three joints. 

 The main stem branches again at the ninth joint on the right hand side 

 from the first axillary, the third and seventh joints of the main stem having 

 syzygies. Only one joint of this branch is preserved. 



At the eighth joint of the main stem, it branches again to the left. 

 The main stem has a syzygy at the second joint. The third branch on 

 the left has syzygies at the second, third, twenty-first, twenty-fifth, 

 and thirty-sixth joints ; it has apparently sixty-eight joints, and seems to 

 be perfect. 



The main stem branches again to the left at the eleventh joint. It has 

 sy^^ygics at the third and seventh joints. The fourth branch on the left 



