NESTS AND EGGS OF AUSTRALIAN BIRDS. 829 



639. — HYDROfHEunoN HYBRiDA. Pallas. (610) 



MAESH TERN. 



Figure. — Gould: Birds of Australia, fol., vol. vii., pi. 31. 



Reference. — Cat. Birds Brit. Mus., vol. .\xv., p. 10. 



Previous Descriptions of Eggs. — I.egge : Birds of Ceylon, p. 999 

 (1880) ; Campbell : Southern Science Record (18S3), also Nests 

 and Eggs .Austn. Birds, pi. 2, fig. 610 (18S3); North: Austn. 

 Mus. Cat., p. 353 (1889), also app. ii. (1890); Hume — Oates : 

 Nests and Eggs of Indian Birds, vol. iii.. p. 305 (1890). 



Geographical Distribution. — Australia in general ; also various other 

 localities in the Old World. 



Ne.sf. — Somewhat symmetrically built of stalks of aquatic herbage, 

 with a submerged foundation, and fringed about with gi-owing grass 

 (" couch ") in a lagoon or swamp. Dimensions over all, including 

 foundation under water, 18 inches in depth; diameter of base at water- 

 line, 16 to 18 inches; diameter of top, which is slightly concave, 8 inches. 



E(/c/s. — Clutch, two to three ; form varies from broad to pointed 

 oval ; texture of shell flue and tliin ; surface slightly glossy ; coloiu', 

 varies from light cold-green to ohve, but is usually a warm greyish- 

 green, spotted and blotched with dark-olive or umber and duU-gi'ey. 

 Some of the markings are fancifully shaped, bold and lai-ge, and, in 

 instances, inclined to cluster round the upper quarter. Dimensions in 

 inches of a series of full clutches : typical (1) 1-57 x 1-09, (2) 1-54 x 1-1. 

 (3) l-.51xM2; small (1) 1-5 x 1-07, (2) 1-45 x 1-05, (3) 1-39 x 1-06; 

 round (1) 1-43 x Ml, (2) 1-41 x 1-08. (3) 1-41 x 1-06. (Plate 23.) 



Observations. — This vridely distributed species is found in Europe, 

 Asia, and Africa, as well as Australia, where it frequents inland watei-s. 

 It is a very beautiful and interesting bird. Its silvery-grey forms 

 may often be seen flying along the course of rivers or hawking over the 

 face of swamps in the interior. I have seen the birds a good deal in the 

 neighbourhood of the Murray River. Unhappily for me, I was either 

 too eai'ly for eggs or missed their favoiu:ite breeding gi'ounds, for after 

 I returned home my friend, Mr. G. H. Morton, kindly sent me the 

 following interesting descriptive sketch, and several beautiful clutches 

 of the Tern's eggs for examination : — " I have found the nesting place 

 of the Marsh Terns. It is the old swamp that I directed you to up the 

 river. I regretted veiy much that you were not with me when I came 

 upon it, as it was as grand a sight as the Ibis rookery we discovered. 

 Just imagine a swamp of about 500 acres in extent, covered with a 

 beautiful gi-een-sward of couch-grass, spangled with the bright star-like 

 3'ellow flowers of the Limnaiifhemum. and hovering over this or sitting 

 on their nests himdreds and hundreds of Terns, while hundreds of Little 

 Grebes were bobbing up and down among them ! At almost every 

 boat's length a Tern's nest was to be seen, with invariably three eggs 



