CLARK ON THE BLACK GUILLEMOT. 85 



But liere, there appejus a divcrj^ciue of method lur C. crocca, Ps. 

 cphippifcr and T. nutri<uis! i)hice the ejigs on the back, where extra plates 

 or extra folds of skin of some sort S(M*ve to protect the younji'. On the 

 other hand /'v. <iiitaictiriis and the four other Ciicaiiiarias mentioned 

 place the e<><>s underneath the hody. In (,'. (jlacialis and C. laevigata, 

 they are there received into two brood i)Ouches Avhich are formed as 

 invaiiinalious of the skin. There can he no doubt, I thiidc, that this brood 

 pouch met hod is a modilication of the sim]>ler ventral brooding of the 

 other species. 



In conclusion it is interesting to note that all of these thirteen species, 

 which care for their eggs and young are either Si/ii(ipti(hv or Dcndro- 

 (■]iirot(i\ and no less than five are ('iicuiiKirhis. 'JMie geographical dis- 

 tribution is aiso jicculiar. for six sjjecies are Antarctic, while three 

 occur on the coast of California; two are ^A'est Indian, one is Arctic 

 and one is found in the Mediterianean. .Vll are shallow water forms, 

 )uost of them littoral, though ('. (jJacialis occurs nearly down to the KM) 

 fathom line, Ch. contort a passes that line and I*s. cptiippifer is said to 

 occur at 315 fathoms. 



BLACK GUILLEMOT. 



Shot in the Detroit river off foot of Lieb street, Detroit, Michigan, 

 December 14th, 1895, owned by Robert McKinnell,- 748 17th street, De- 

 troit, Mich. Mounted by Charles Lunimcr, taxidermist, 354 Monroe 

 avenue, Detroit. Communicated by O. A. Farwell. 



