274 



AMPHIPNEUSTA. — PROTEID^. 



figures. The large oval figures exhibit their 

 form as seen directly and sideways ; the smaller 

 ones represent the human blood-disk for the pur- 

 pose of comparison ; both are magnified seven 

 hundred times in linear dimensions. The blood 

 from which the former figures were taken was 



BLOOD-DISKS OF SIREN AND OF MAN. 



obtained from one of the external gills of a Siren 

 lacertina twenty inches in length, which was then 

 (1841) living at the Zoological Gardens, Regent's 

 Park. Though subjected to examination imme- 

 diately, the large figure shows, in the crossing 

 lines, traces of folds produced by the partial 

 drying of the external capsule. 



The species contained in this Order are very 

 few, and compose but a single Family, Proteidce ; 

 they are rather large animals, of dull sluggish 

 manners, much resembling eels in form, with 

 minute rudimentary feet, inhabiting the mud of 



