c ULAMOCRINUS DIOMED I 17 



the two interradials of Apiocrinua insignia (See de Loriol, Plate 56, 

 Fig. 2°.) The second radial in Byocrinus is not wide, bul narrow, 

 Calamocrinus, a feature which, according to Carpenter, is also charac- 

 teristic of Millericrinus Milleri, and a few other species. 



The calyx, though symmetrical in all Neocrinoids, may undergo distor- 

 tion (Eugeniacrinidse, Holopidae). In Thaumatocrinus and in Calamocrinus, 

 though to a less extent, the anal radials arc larger than the others.* 



The Arms. 



Calamocrinus has Eve arms (Plate II. Figs. 1. 2. Plate III. Figs. 1-3. Plate 

 VI. Fig. 1 i. ami. as far as we can judge from the fragments of the arms which 

 could he reconstructed, there are three lurks to the right and two to the 

 left in one case (Plate I. Fig. 1). but in the adjoining arms of the same figure 

 there were evidently three branches on the left and two on the right. 

 Judging from the specimen figured in Plates II. and III., the first branch of 

 the anterior arm was to the left (facing it). The same was the case with the 

 left anterior and the left posterior, while in the right anterior arm the firs! 

 branch was to the right. In the anterior and left posterior arms the first 

 axillary was the seventh brachial joint (Plate III. Fig. 2): the same was the 

 case in the right and left anterior arms. In another specimen the axillary 

 of the same arm was the eighth brachial, there being three syzygies in 

 tins arm. in the first, fourth, and sixth brachials, while in the former ease 

 there were three syzygies, in the first, fourth, and fifth brachials. We find 

 the same difference in Plate I. Fig. 1, and in Plate IV. Fig. 1. The second 

 axillary (Plate II. Fig. 1) is the (twelfth brachial) fifth joint from the first 

 axillary in both the anterior and the right anterior arms, while in Plate 

 IV. Fig. 1, it is the sixth joint in that arm. The third axillary is again the 

 sixth joint from the second, while the fourth axillary is the eighth joint 

 from the third axillary. In Plate II. Fig. 1, the second, third, and fourth 

 axillaries are on the same joints as those of the arm of Plate IV. Fig. 1, 

 while the fifth axillary is the eleventh joint from the fourth axillary. In 

 the right arm of Figure 1, Plate I., the arrangement of the axillaries is the 

 same, but the fourth axillary is the ninth joint from the third axillary, and 

 not the eighth. 



In the arms in which there are seven joints to the first axillary there 

 were syzj'gial joints on the first, fourth, and sixth joints. In the same arms 



* See also Carpenter and Etheridge, Ann. Mag., 1871, p. 285, Allagecvinus. 

 3 



