324 



SCANDINAVIAN FISHES. 



in the same space Reijalecus capensis should only possess 163 rays; 

 and in a specimen of Regalecus glestie from Bohuslan this space should 

 presumably contain only 103 rays. Thus we might here expect to 

 find a specific distinction expressed witliout difficulty; but in fishes 

 of so loose a structure as these, and considering that in Regalecus 

 (jlc.vie we are compelled to recognise a variation in the rays of the 

 dorsal tin so considerable as to range between 200 and 400, the dif- 

 ference in the degree of contraction of the body may considerably 

 affect the results arrived a(, and the individual variations render the 

 character wortldcss. As n general rule we may reasonably assume 

 that the rays of the dorsal fin are more densely set in young speci- 

 mens; but in the largest example known, Lindeoth's specimen from 

 Hittereii, there are 47 rays in a sjiace which in the Royal Museum's 

 smaller specimen, from BohusLin, contains only 40 rays, and accord- 

 ing to CoLLETT, in the Stavanger specimen (1881 — Stavanger Mu- 

 seum), which in size was probably almost exactly intermediale between 

 these two specimens, tliere are on an average 43 rays in a similar 

 portion of the dorsal fin. 



The relation between these three specimens thus contradicts the 

 above rule; and a further example of the individual variations may 

 be found in the Regalecus from the waters between the coasts of 

 Tasmania and Victoria, in Jlay 1878, which specimen McCoy (1. c.) 

 referred to the same species as the Atlantic King of the Herrings, 

 assuming that the identity of the species may be defended, as seems 

 not improbable. This .Australian Regalecus was only 414 cm. long, 

 and only an insignificant part of tlie tail was wanting (the last re- 

 maining ray of the dorsal fin was only 2 mm. long and the tail, at 

 tlie point of fracture, only 13 mm. deep). It was thus at least 1 

 metre shorter, though more nearl}- perfect, than the Hitteren specimen; 

 but it had 406 dorsal fin rays, in addition to the 17 rays of the high 

 occipital fin. In the shape of the body — which was, liowever, con- 

 siderably shallower, a characteristic which McCoy supposes to belong 

 to the male — in the coloration and in other respects" this Regalecus 

 so closely resembles the Atlantic species that it is only our insufficient 

 knowledge of the latter species that calls for caution in the identi- 

 fication of two species from localities so distant. 



We may still acknowledge the truth of Nilsson's words: "It is 

 impos.sihle strictly to define the distinction between the species of this 

 genus". But it seems most probable that as yet we know only one 

 species of the genus; and the fragmentary knowledge we possess of 

 tlic adult stages of this species — no entire specimen of the Atlantic 

 llegalecus glesne has yet been scientifically examined — maj' safely 

 be supplemented from tlie better-preserved specimens of the Mediter- 

 ranean and Australia. 



The Royal Museum possesses the remains of two specimens of 

 Regalecus glesne. Of the first specimen, which was found on the 12th 

 of August, 1797. oft' the island of Hitteren, near Trondhjem, and 

 which was tlie original of Lindroth's description and figure (1. c.) of 

 Ggmnetrus Grillii, there is left only the skin of the left side behind 

 the head and the ray of the left ventral fin. This jiart, which was 

 stuifcd by LiNDiiOTH for Grill's museum at Soderfors, is nailed to a 

 lioiird. The head and the dorsal fin are artificial, as they are shown by 

 Li.NiiRiiTH in his figure of the stuffed specimen. This example is re- 

 markable in several respects. It is the longest specimen hitherto pre- 

 served and examined. The number of rays in the dorsal fin is greater, 

 and tlic vent is situated farther forward, relatively to the length of 



the body, than in any other Atlantic specimen on record. The last 

 two characteristics may thus be interpreted as expressions of the 

 changes of growth; but the difference between it and the other At- 

 lantic specimens in these respects is so great that some standard by 

 •which to test the correctness of the description, may well be required, 

 and the specimen fortunately offers us one, even in its incomplete 

 state. The interspinal hones are still to be found at the dorsal edge, 

 throughout the greater part of the length of tlie body, and, posteriorly 

 at least, are so distinct that they may he counted without difficulty. 

 The total length of the base of the dorsal fin left is 515 cm. The 

 part occupied by the last 100 interspinal bones measures 945 mm., 

 bj- the next 100 in front of them 1,305 mm., and by the next 100 

 1,505 mm. The remaining 1,395 mm., where the interspinal bones are 

 now partly indistinct, can hardly have contained less than 106 rays, the 

 number of artificial rays set there by Lindroth. It is, therefore, highly 

 probable that Lindroth's statement that the dorsal fin contained 406 

 rays, is based on his examination of the fresh specimen, just as it was 

 when he received it and before the dorsal fin was lost. This assump- 

 tion finds strong support in McCoy's description of the Australian Rega- 

 lecus, which had still more rays in the dorsal fin. Again, with re- 

 gard to the position of the vent Lin'DROTh gives a definite measurement 

 (4 Sw. ft. 7 in. ^= 1,361 mm.) of the distance between it and the 

 head, a statement which almost exactly applies to the stuffed skin, 

 where the vent itself is 25 mm. long, and is stopped with red putty. 

 This distance is indeed less in proportion to the length of the body 

 than in any other specimen known (nearly 25*/.2 %, instead of the 

 usual average 34',', %); but in proportion to the depth of the body 

 as given by Li.vdroth (25'/., 'i of this distance) it corresponds fairly 

 closely to the same measurement in several of the specimens best 

 known in this respect''. 



The second specimen in the possession of the Royal Museum is 

 the only Swedish specimen of Regalecus glesne discovered up to the 

 present date. It was found on the 28lh of March, 1879, about 3 

 miles west of Koster, on the shore of an islet called Burholni, and 

 secured for the Museum by Mr. G. v. Yhlen, Inspector of Fisheries. 

 The greatest depth of the body, according to Coastguard M.vrTSON's 

 statement, was a little more than a foot (3 dm.) and the thickness 

 about 4 in. (1 dm.). The length was 25';^ ft. (?). The colour was 

 "grayish (Ui the sides and white on the back, covered with a bright 

 dust''. A fin 3 in. (75 mm.) high ran from the occiput to the tail. 

 When the specimen was secured for the Royal Museum, however, it 

 had been considerably damaged by the surf and the ravages of birds. 

 The upper part of the black forehead, with the groove for the nasal 

 processes of the intermaxillary bones, is, however, preserved, and on 

 the occiput we can find traces of the anterior fin-rays, the first of 

 which points in a forward direction and is set at the end of the 

 groove just mentioned. The rest of the head is crushed to pieces, 

 and the nasal region, with all the jaw-bones, is wanting. The re- 

 mainder of the body from the first ray of the dorsal (occipital) fin 

 is 245 cm. in length, and the greatest depth, which occurs at a dis- 

 tance of from 5 to 11 dm. from this ray, is 29'/., cm. At this 

 point the lateral line (fig. 88, a) lies at a distance of 70 mm. from 

 the ventral edge and 226 mm. from the dorsal. The greatest thick- 

 ness is now onlj' 36 mm.; and, according to Mattson's statement, the 

 body has thus shrunk to '/j of its original thickness. The gill-rakers, 

 42 in number, may be counted on the first branclnal arch. The}- are 



" According to McCoy's nu'asurements the length of the head is greater tlian llic depth of tlie l>ody; but the figures show that he 

 took the length of the head when the mouth was protruded. 



'' The greatest depth of the body in 'i of the distance between the head and the vent measures, according to published statements, 



ill the spei'imen from North Fjord (1855 — Bergen Museum) 24'9 



., ., ,, Langesund (1822 — Christiania Museum). ,_ 26'5 



,, ,. Grovie (1844, see Richardson, Sujiiil. to Yarh., Brit. Fish.) 26'1 



.. .. „ .. the Cape of Good Hope (1868, see Layard, Proc. Zool. Soc.) 25'n 



