THE OOLOGIST. 



J27 



■aed at the expence of much time and by 

 tising great patience. In a great mauy- 

 reeclj'-shored lakes and ponds here in 

 the southern part of the Lower Penin- 

 sula of Michigan, these birds may be 

 founu breed ng. In fait, whenever 

 found consorting in the mouths of June 

 and July, it is reasonable to expect that 

 they are nesting in the immediate vicin- 

 itj' and proljably on the same pond or 

 lake. This diver is Init very little given 

 to Hying except during migration and 

 I have but rarely oliserved its tiying 

 about during the nesting season. The 

 Great Northern Diver often feeds on 

 lakes several miles distant from the 

 small lake or pond on Avhich it builds 

 its nest, but the Dab-chick is nearly al- 

 WAys found about its nesting site. 



The song of the common Hell-Diver 

 is well known to most col ectors, and 

 by it the egj-hunter may be attracted 

 to the mud hole where the bii'ds are 

 nesting. It is eutirelj' different from 

 all other notes with which I am ac- 

 quainted. But though so peculiar, I 

 cannot describe it satisfactoril}'. 



Nests have been found at the edge of 

 mere mud-holes not over a half acre in 

 I'Xtent. Then again I liave found nests 

 at the edge of large interior lakes. As 

 a rule, however, the birds seeni to favor 

 -mall lakes or ponds which are more or 

 less covered with lily-pads and sur- 

 rounded with marshy l)orders. 



The spot cho.sen is never situated like 

 thai adopted by the larger relative, the 

 Loon, but is always near shore or right 

 II the boggy margin. In such a loca- 

 iiona mass of matter is accumulated, 

 formed principally of decayed and sod- 

 den grass, rushes, reeds and weeds. 

 This mass is generally m >re or less sup- 

 ported by the natural accumulations 

 found in stagment bodies of water, Ijut 

 -ometimes the mass tloats, I am inform- 

 ed. In all ne.-ts that I have seen the 

 structure was anchored by rushes, roots 

 and other material or more often was 

 situated on a comparatively firm founda- 



tion like the bog which holds the eggs of 

 the Loon. In, or on this mass of vegeta- 

 ble material, mixed with mud aud ooze 

 from the bottom of the lake, the eggs 

 are found. The structure, or mass 

 for I cannot call it a nest from auj- ap- 

 pearance or resemblance to any nest 

 that I have ever found, is always wet 

 and soggy and to me is aljout the most 

 uninviting place possible for a bird to 

 deposit' her eggs in. 



The Hades Plunder, however, evi- 

 den ly thinks the situation salubrious, 

 and on this mass of rotting material the 

 eggs tivc to eight in number are laid. 



Six eggs is the usual number I believe, 

 though seven eggs is not I'are, while 

 many nests are found containing but 

 live I have never found a smaller 

 number in a completed set. The earli- 

 est date of finding a complete set was 

 May twentieth. These eggs are gener- 

 ally of a dull yellowish, white or bluish 

 white, when first laid, but soon get 

 daubed and bernished with the mud 

 and rotting vegetable material with 

 which the set is covered whenever the 

 old bird leaves the nest. Often the 

 eggs which are covered more or less 

 thickly with a coating of calcareous de- 

 posit, is tinged with a very fair blue 

 cokring, sometimes nearly equaling 

 the blue of a i)lack-billed cuckoo's egg. 

 This variation in external coloration is 

 not foun.J in more than one in fifteen 

 eggs. If the chalky coat is scraped ofl', 

 the i)roper color of the eggs may be seen 

 nearly always buish, and it is my ad- 

 vice to collectors to scrape one or two 

 eggs in a set to show the true inner 

 cohjr. We may compare tiie work to 

 the polishing of shells, which, while it 

 decreases their value, as considej'ed by 

 the naturalists, certainly enhances their 

 appearanc(N and assists in beautifying 

 the cabinet. 



The last of May or early part of 

 June is the time to secure comjdete sets 

 of eggs. I have four seta of six and one 

 of seven eggs taken May 31, 1888, and 



