HARDWICKE'S SC lENCE -GOS SIP. 



251 



to whom I have submitted it, has come to the same 

 conclusion respecting it. I have written to one of 

 my collecting acquaintances at Plymouth concern- 

 ing this plant, directing attention to the spot on 

 which it was found a month ago ; and if I should be 

 so fortunate as to receive some fresh specimens of 

 it, I hope to be able to trace its history more com- 

 pletely than I have been capable of doing hitherto, 

 although, as in the case of the Mediterranean 

 species, Polysiphonia divergens (which was taken 

 some years ago in Falmouth Harbour, and identified 

 by Mrs. Merrifleld),the curious Melanosperm I have 

 described, has certainly been developed from spores 

 which have been borne in currents from some foreign 

 habitat, and vegetated in a similar situation here to 

 that in which the parent plant has been growing. 



W. H. Grattann. 



THE GREAT NORTHERN DIVER. 



AWAY amid the desolate solitude of the cliifb 

 and headlands that shield the Western He- 

 brides from the inroads of the tempestuous Atlantic, 

 there may occasionally be discerned, during the 

 declining and colder portions ox the year, a tall, 

 gaunt, snowy-breasted sea-bird sitting erect upon 

 the ledge of some wave-lashed rock. He sits there 

 solitary, yet still not destitute of company ; and 

 the conspicuous whiteness of his breast contrasts 

 strangely with the sombre aspect of the cliff's 

 behind. He sits motionless, too, and apparently 

 immersed in a "brown study"; but his keen 

 bright eyes are all the while intently occupied in 

 ministering to the comfort of number one. Perhaps 

 he is not in his proper place. That may be, and 

 indeed our conjecture is not altogether unsupported 

 by fact ; lor after a little while, when appearances 

 manifestly assume a favourable aspect, he darts 

 with great grace and facility into the sea. He has 

 traversed the watery regions with truly marvellous 

 swiftness ; for in the course of about two minutes 

 he reappears about two hundred yards away from 

 the point of ingress. The elongated jacht-like con- 

 formation of his body, conjoined with the power- 

 ful action of his short wings and suitably-placed 

 feet, have proved valuable auxiliaries to him in 

 the course of his aquatic excursion. Moreover, 

 he is a very beautiful and exceedingly knowing- 

 looking bird. Yet it may be asked, if our bird is 

 capable of expending such a vast amount of physical 

 energy as that now indicated, may not this valuable 

 endowment be also utilized in some other mode or 

 direction ? Yes it may ; for it is well known that 

 our diver, except during the breeding season, is a 

 constant frequenter of the open sea, where he is 

 frequently to be seen hovering about in the vicinity 

 of herring and sprat shoals, diving amongst them, 



and abstracting therefrom as much nutriment as 

 sufBces to renovate and sustain the immense physical 

 force involved in his method of living. 



It is chiefly, however, amid the vast solitudes of 

 the Arctic regions that the Great Northern Diver 

 is most frequently to be discerned. The coasts of 

 Labrador, Iceland, and Spitzbergen are the parti- 

 cular localities where he loves to settle, especially 

 during the breeding season, which occurs once in 

 the year — generally in the summer. There they 

 may readily be discovered, in company with a few 

 co-mates, ranged in vast numbers along the shore, 

 busily occupied in the pursuit wherewith their 

 name is most intimately associated. As soon, how- 

 ever, as the southward career of the sun has per- 

 mitted autumn to descend upon the temperate 

 regions of the earth, the breeding duties having 

 terminated, our bird emerges from his ice-bound 

 home, and travels downwards till about the fifty- 

 second degree of north latitude. During the autumn 

 and winter months, he is frequently to be seen in 

 the neighbourhood of the Faroe Islands, the Shet- 

 land, the Orkney, and the Western Islands, the 

 coast of Sutherland, the Frith of Forth, &c. He is 

 also commonly noted on the Irish, and even on the 

 Welsh, coasts. According to the testimouj^, how- 

 ever, of some observers, he breeds on the Faroe 

 Islands, and is to be seen there all the year round. 

 The bird now under review belongs to the highly 

 interesting order entitled Natatores. Furthermore, 

 it is enrolled in the genus Colymhus, belonging to 

 the sub-family Cohjmbince of that order. The specific 

 name is glacialis, which has probably been allotted 

 to this bird on account of its association with the 

 ice and snow of the polar regions. The genus 

 Colymbus is broadly distinguished by the possession 

 of short wings ; broad, flat, compressed tarsi, which 

 are placed so very far backwards that the animal 

 always assumes a very erect position when standing 

 thereon ; and a strong, straight, rather compressed 

 bill, pointed at the tip. 



We shall now briefly indicate some of the prin- 

 cipal external peculiarities whereon the specific 

 characteristics of our bird depend. These are as 

 follows : — Beak, head, and neck of black colour, 

 with the exception of two crescent-shaped rings of 

 white, streaked with longitudinal black bands (one- 

 situated immediately beneath the head ; the other 

 at the lower end of the neck) ; the general colour 

 of the breast is a pure white, but there are a num- 

 ber of vertical black lines on the upper portion 

 thereof. The colour of the back, tail, legs, and 

 feet, on the other hand, is black or nearly so, with 

 the exception of white spots on the following parts; 

 viz. — On the broad back itself, where, however, 

 the spots are very small (as also on the wing- 

 coverts, rump, and upper tail-coverts) ; the scapu- 

 lars and tertials have large white square spots— the 

 latter feathers also ending in white. The total 



