290 Transactions. — Zuologij. 



ing takes place at the beginning of September. Breeds on 

 one island only, and not in great numbers. None have struck 

 the lantern. 



Puffinus assimilis. 



Not very numerous, though it breeds on all the Moko- 

 hinou Islands. The burrow is generally under a rock, in 

 the interstices between rocks, or less frequently on the level 

 ground below a root or tussock. The nest is at all times diffi- 

 cult to get at — more so than that of any other species which 

 breeds here. Burrowing commences in April and May, and is 

 carried on at night only, so that the birds are rarely found in 

 the burrows during the day, previous to laying. Nesting-ma- 

 terial is deposited in the burrow during June and July, and at 

 the end of the latter month laying commences, and extends 

 to the middle of August. A single egg only is deposited in each 

 nest. Colour of egg, white; length, 2-3in. ; width, l-4in. The 

 young in down are greyish-black, excepting a narrow line of 

 white on the throat and breast, wdiich on reaching the abdo- 

 men divides into a right and left branch, uniting again behind 

 the vent, thus leaving the abdomen grey. When the young 

 birds depart they can scarce be distinguished from the old. 

 They begin to leave in the end of December, and by the middle 

 of January all have departed. This species very rarely comes 

 against the lantern, and the burrow is seldom higher than 60ft. 

 above the water. 



Puffinus tristis. 



Between the 3rd December and the 15th January, 

 1886-87, I found the nests of a species of Puffinus which 

 differed somewhat from P. tristis as regards colour and 

 measurements, and also in this : that the colour of the egg of 

 the Mokohinou bird is white. I sent a skin to Mr. T. F. 

 Cheeseman, F.L.S., who informs me that he has compared it 

 with others undoubtedly P. tristis, and, allowing for indi- 

 vidual peculiarities, finds them identical. 



It is a rare bird here, and confines itself to three small 

 patches of ground on different islands, only a few nests being 

 found on each, and these not far apart. 



The biUTOW is from 4ft. to 9ft. in length, and formed 

 in such a way that the nest is between 2ft. and 3ft. under 

 the surface, so that to get at the egg a pick or spade must be 

 employed. This has invariably been the case in all I have 

 examined, no matter whether the burrows were situated on 

 rising or comparatively level ground. Long llax, growing in a 

 deep light soil, is characteristic of the several breeding-places. 

 In two burrows, which I dug out in December, a bird was 

 found in eacb, sitting on an egg just laid ; whilst in six others 



