484 ME. S. GRIEVE ON THE DISCOTEET 



few sea- and land-sliells intermixed ; but no implements or other 

 remains have yet been met with in these lower deposits. The 

 conclusion that all seems to point to is, that the lower part of the 

 Caisteal-nan-Grillean has been formed bj natural, and not human 

 agency. 



Garefowl-bones described by Mr. Gibson (see Plate IX.) : — 



1. JRiglit humerus, measuring 4 inches in length, and 1 inch in 

 breadth at the proximal end. The compressed shaft at its middle 

 portion measiires 6 lines in long diameter, and nearly 3 lines in 

 short diameter. According to Professor Owen (Trans. Zool. 

 Soc. vol. V. p. 327), there is a thick ridge or raised rough surface 

 near the radial end of the articular head of the humerus, extend- 

 ing about 8 lines down the bone, which gives insertion by a well- 

 marked narrow elliptical depression to the second pectoral muscle, 

 the raiser of the wing. In the present specimen the bone of the 

 ridge exhibits a diseased condition, the normal depression being 

 changed into a deep trough 8 lines in length and 4 lines 

 broad. 



2. Proximal half of rigid humerus. — Total length of specimen 

 2\ inches ; broken about the middle of the shaft, which exhibits 

 medullary cavity. This cavity measures 2| lines in long diameter 

 by 1 line in short diameter, the shaft measuring similarly 6 lines 

 by 2^ lines. 



3. Distal half of left humerus. — Specimen measuring 2 inches 

 2 lines ; shows medullary cavity. In this specimen the condyle 

 and the three anconeal ridges are very perfect. 



4. Distal end of left humerus, 3 inches in length. 



5. Left coracoid hone, with a total length of 2 inches 4 lines. 

 At the sternal end it is 10 lines in breadth ; but as both ends are 

 imperfect, it probably had a breadth of at least 1 inch. The thin 

 lamellif orm process given off above the sternal articulation is also 

 gone ; otherwise the coracoid is entire. Prom the sternal end it 

 gradually contracts to 5 lines, then widens out, giving off a strong, 

 compressed process, which is perforated. 



6. Upper half of right coracoid. — Specimen 1 \ inch in length, 

 ending a little below the perforated process. 



7. Distal end of right ^i5^«.— Specimen 1 inch in length ; shaft 

 showing very minute medullary cavity. 



8. A dorsal vertebra. 



In addition to the above, Mr. Galloway has likewise discovered 

 a number of other remains, among which we may mention several 



