1890.] ON BONES FROM THE NITRATE BEDS OF PERU. 375 



Fig. 11. Ouimatidium of ^. spiTiosiis, from a teased and depigmented prepa- 

 ration. 



12. Vitreous body of A. briomoiis, from above. 



13. Ommatidium of A. brunneus, from a teased and depigmented prepa- 



ration. 



14. 15, 16. Transverse sections tlirougli ommatidium of A. furcatus at 



different levels. 



4. Note on the Bones of small Birds obtained by Professor 

 Nation from below the Nitrate-beds of Peru. By 

 E. T. Newton, F.G.S., F.Z.S. 



[Received April 17, 1890.] 



At the meeting of the Zoological Society held on the 1 4 th January, 

 1890, Dr. Sclater exhibited some bones of small birds sent to him by 

 Prof. Nation in a small quantity of guano-like earth obtained from 

 " beneath the nitrate-beds of Peru." At present we have no infor- 

 mation as to the precise locality where these specimens were found, 

 and although the nitrate is now being extensively worked, little 

 seems to be known as to the age of the deposits ; some account of 

 them, however, has heen published by Mr. Ralph Abercrombie in 

 ' Nature' (June 20 and July 25, 1889), and he alludes to the fact that 

 there is "in some deposits a layer of guano under the caliche 

 (nitrate);" but this is not always the case. 



The specimens were handed to me by Dr. Sclater for further 

 examination, and by sifting the guano several other bones were found, 

 so that there are now for examination portions, more or less complete, 

 of the following: — 3 femora, 4 tibio-tarsi, 7 metatarsi, 2 or 3 fragments 

 of pelvis, 8 humeri, 4 ulnae, 3 metacarpals, and 2 coracoids. The 

 only portions of the head found are the curved extremities of 3 

 upper bony beaks, a fragment of a horny beak, the hinder ends of 

 two mandibular rami, and a quadrate bone. There are also portions 

 of 3 vertebrae. 



With regard to the lengths of the long bones, it is only the femora 

 and metacarpals which are quite entire, but by comparing the 

 different examples of each of the other bones, a tolerably accurate 

 idea of their length may be obtained, and the following measurements 

 were made before I had seen those of the Cymochorea leucorrhoa 

 given by W. A. Forbes (Memorial Volume, p. 426, 1885), which are 

 here reproduced for comparison. 



Bones from below Cymochorea leucorrhoa, 



nitrate-bed. after Forbes, 



millim. millim. 



Femur 16 16 



Tibio-tarsus 37 ? 37 



Tarso-metatarsus 25-30 24 



Humerus 37-42 35 



Ulna 35-40 35 



Metacarpal 20 manus 42 



Coracoid 13-15 



26* 



