884 Transactions.—Zoologiy, 
ProceLtara arris, Buller, Trans. N.Z. Iost., Vol. VIL, p. 215. 
Sr. nov. Supra saturaté cinereus ; dorsi plumis et supra-caudalibus 
nigro terminatis ; alarum minimis et ald spuriá nigrieanti-brunneis; pri- 
mariis extüs nigricanti-brunneis, intüs albis; secundariis pallidà cinereis, 
albo angusté marginatis, basaliter albis; rectricibus saturaté cinereis, 
duabus externis intùs albidis; fronte alba cinerascenti-nigro variá; regione 
suboeulari conspieué cinerascenti-nigré ; facie laterali guttureque albis; 
pectore imo et abdomine cinereis plumis basaliter albis; corpore reliquo 
subtùs alba, pectoris lateribus cinereo lavatis, hypochondriis et subeaudalibus 
inferioribus cinereo variis ct minute trausfasciatis ; subalaribus albis, exte- 
rioribus conspicué nigrieantibus : rostro nigro : pedibus sordidé flavis, 
digito externo et membranis interdigitalis nigris. 
Dr. Finsch suggests that my P. affinis, as described above, may turn out 
to be D. mollis. I am unable at present to adopt this view, and for tho 
following reasons :— 
Procellaria mollis (the soft-plumaged petrel) was discovered by Mr. Gould, 
who first described it in the Annals and Magazine of Natural History (Vol. 
VIII., p. 868), and afterwards figured it in his Birds of Australia, Vol. VIL, 
pl. 50. In his Handbook, at page 454, Vol. II., he has given a full descrip- 
tion of the adult bird, from which I take the following particulars, by way 
of comparison :—Total length 184 inches; wing 92; tail 5; tarsus 1$. 
My bird has an extreme length of 18 inches, the wing (from the flexure) 
measures 10:5, the tail 4, and the tarsus 1:2. It will be seen, therefore, 
that taking the two birds to be of somewhat equal size, (the Jength of a 
dried specimen being always an uncertain measurement), Procellaria mollis, 
with a wing nearly an inch shorter than P. affinis, has a decidedly longer 
tarsus and the tail a full inch longer. Ina group of birds, where tho 
species are so closely allied, this test of relative proportion in the functional 
parts is, I consider, a sound means of discriminating species. The plumage 
of D. affinis has a close general resemblance to that of three other allied 
species, forming together, as I have before pointed out, 2 very natural 
group or sub-genus. In the full deseription which I have reproduced above, 
there are some details of colouring which are, I think, due to immaturity, 
but the general plumage comes nearer to P. cookii than to P. mollis, 
although in other respects, as pointed out in my original description of the 
new bird, the two forms are specifically distinet and easily discriminated.* 
* Since writing the above, I have received from Mr. C. H. Robson a Petrel answering 
exactly to my P. c finis, with the slightest possible variation in the measurements. This 
was obtained at Cape Campbell; but Mr. Robson writes me (under date June 3) that he 
has secured another, which etruck the Moeraki Lighthouse in thick weather and was 
killed, 
WA ES (a E T ER 
