Bibliographical Notices. 285 



Springer in thus rendering themselves liable to adverse criticism ; 

 and the same remark applies to various other morphological state- 

 ments on their part. 



They think that they have discovered a method of inferring the 

 presence or absence of uuderbasals, more especially in those types 

 which have the lower part of the calyx partially concealed. They 

 give the following general rules, to which they " have not found a 

 single exception among all Pala3ocrinoidea " (pp. 7, 8): — 



"1. In species with underbasals, whenever the column is pent- 

 angular, its longitudinal angles are directed interradially, the sides 

 and columnar cirrhi radially : on the contrary, in species with basals 

 only, those angles are radial, the sides of the column and the cirrhi 

 interradial. 



" 2. When there are underbasals and the column is pentapartite, 

 the five sections of the column are radial, the longitudinal sutures 

 interradial, the radiation along the axial canal radial ; but the 

 opposite is the case when basals only exist." 



8o far as we are aware, the first of these two rules always holds 

 good among Palteocrinoidea ; but there seems to us to be something 

 seriously wrong about the statement of the second. It is illustrated 

 by two figures on pi. vi. : fig. 15 is said to represent the " Basals of 

 Barycrinus, with the joint of the quinquepartite column." No basals 

 are shown in the figure, however, but only the underbasals («) and 

 the five sections of the first columnar joint (c). The arrangement 

 of the figure is as follows : — the five sections of the stem are inter- 

 radial, its longitudinal sutures radial, and the processes of the axial 

 canal also radial. This (if correct) would suggest a lapsus calami in 

 rule 2, the words radial and interradial having been transposed ; and 

 an examination of fig. 13 confirms this idea. It represents the basals of 

 an undescribed monocyclic genus {Stenocrinus) with a quinquepartite 

 column. The sections of the column are radial and the sutures 

 interradial, whereas exactly the reverse ought to be the case accord- 

 ing to rule 2. Apart from this unfortunate transposition, however, 

 fig. 13 (if correct) shows that there is at least one exception to a 

 part of rule 2, for the processes of the axial canal are radial both in 

 fig. 13 and in fig. 15, whereas according to rule 2 they oiight only 

 to be so in the latter (Barycrinus). 



This question is further complicated by the fact that in the 

 " Diagram of Barycrinus,'' which appeared on pi. i. of the first 

 part of the ' Revision,' the processes of the axial canal are interradial. 

 Which of these two figures of Barycrinus is the correct one, the 

 first or the second ? 



A precisely similar transposition to that just mentioned occurs in 

 Part I. of the '■ llevision ' (p. 101). The sections of the column of 

 Bari/crinus are there said to be radial, while " the sutures ai-e inter- 

 radial, the opposite of Heterocrimis, in which they are radial." 

 On p. 64, however, the ridges of the column of the latter genus are 

 said to be radial, which would give the sutures an interradial posi- 

 tion. The figure in Part III. of the " Basals of Heterocrimis, wiht 

 a joint of the tripartite column " (pi. vi, fig. 14) is also rather 

 puzzling, because neither sutures nor sections have either an inter- 

 Ann. & Mag. N. HisL Ser. 5. Vol. xvii. 20 



