BOTHRIOLEPIS HYDRO PI 1 1 LA. 



L25 



dorsal aspect; breadth of dorsal part of body-carapace equal to its lengl li ; posterior 

 median dorsal and posterior part of anterior median dorsal plates distinctly carinate; 

 external surface of body-plates covered with a reticulate sculpture, which is in 

 places slightly nodose; proximal part of pectoral appendage rather broad and 

 relatively long, being nearly twice as long as the distal part, and having a row of 

 specially strong- denticles along its outer margin. 



Description. — The head is shown in PI. XXX, Fig. 2, in impression in Fig. I, 

 and in restored outline in the appended Text-figure G2, and shows this peculiarity, 

 that in no specimen have I been able to discover any commissure of the lateral line 

 system across the pre-median plate in front of the orbit. The plates filling the 

 orbital space are, however, pretty well exhibited in Fig. 2. 



Fig. 62. 



Restored outline of the dorsal surface of Bothriolepis, hydrophila, from specimens in the Royal 

 Scottish Museum, a., anconeal ; a.m.d., anterior median dorsal; a.d.l., anterior dorso-lateral ; 

 or., articular; m., marginal; p. d. I., posterior dorso-lateral ; p. m. d., posterior median dorsal ; p. r. I., 

 posterior ventro-lateral. 



The dorsal aspect of the carapace is also shown in Fig. 2, and we have a very 

 good impression of it in the left-hand specimen on the slab depicted in Fig. 1. 

 The anterior median dorsal plate is worthy of attention, as in most cases a right 

 and left shallow-pointed depression, passing backwards and inwards from the 

 anterolateral angle, meets its fellow of the opposite side at an angle in the middle 

 line about the junction of the anterior and middle thirds of the plate, the two 

 depressions bounding between them a gently convex triangular portion, with 

 baclcwardly directed apex. This is seen in Fig. 2, but more especially in the 

 detached plate from Clashbennie represented in Fig. 3. Behind this the posterior 

 third of the plate shows a distinct median carination, which is continued backwards 

 on the posterior median dorsal. The other plates of the dorsal surface show 



