Terns of the Weepecket Islands, JMassachusetts. 97 



of the eggs is not clear. Perhaps she has not had time to 

 complete her line of research yet. 



It is also common knowledge that the downy young are pro- 

 tectively colored while on the beach, the mottling of the downs 

 with tawmy and dusky producing the effect of pebbles and 

 small stones, and sea weed. It is interesting to notice that 

 while the downy young of the Common Tern are thus mottled, 

 the downy young of the Roseate Tern are longitudinally 

 streaked from head to tail, the whole effect being decidedly 

 darker. Incidentally, the legs and feet of the Roseate are dark, 

 but of the Common almost orange, in the downy young. In 

 both species the throat is dusky black, but the rest of the un- 

 derparts, including the under side of the wings, are pure 

 white. An explanation of this difference in pattern of colora- 

 tion in the downy young of the two species is found in their 

 habits and surroundings. I found young of the Roseate only 

 on the uplands or among the weeds and grass of the upper 

 beach slopes, always more or less concealed by the grass or 

 w'eeds. Here the colors blend well with the surroundings. 

 Many of the young of the Common Tern were on the beach 

 and could be seen there with difficulty ; but those which occu- 

 pied the upland nests, or crouched among the grass and bushes 

 were usually readily seen, because the mottled downs rather 

 contrasted than harmonized with the surroundings. One is 

 almost forced to the conclusion that the traditional nesting 

 place of the Roseate is among grasses, while that of the Com- 

 mon is on the beach among pebbles and sea weed. 



My work was a minute study of the nestling and juvenile 

 plumages, but the results of that work can better await a more 

 careful treatment than the limits of this paper make possible. 

 It is sufficient to say that the body and inner wing markings 

 ol the juvenile Common Tern, on the dorsal side, give the effect 

 of dark bars on a tawny or buff'y ground, while the markings 

 in the same regions of the Roseate give the effect of mottling 

 in tawny and dark gray. As the two species crouched in the 

 grass often side by side, it was easy to compare the relative 

 protective effect of the two plumages which are really so 

 much different in general effect. On the whole, it was a little 

 more difficult to detect the young Common Tern than the 

 young Roseate in the grass and bushes, but the young Roseate 



