198 



tilis tlmii ill I'etr. I'laiieri. Its length %aries here too 

 between about 10 and 8 % of that of tiie body. Tlie 

 aniil aperturi' also occuiiics tlic same i)ositii)li as in tlu' 

 Sea Lamprey Imt the urogenital |>a]iilla is fr(.in.i>;i,lly 

 more developed, es|)eeially in retr(iiii//.:(iit I'Idiicri. and 

 longest and most pointed (projecting far baek), as 

 usual, in the males. Besides this .sexual character may 

 be observed dui'ing the breeding season, I'spcciallx in 

 the females, an Indropical ttiinidit\- of the skin (hg. 

 3411), in particulai' round tlie anus and along tlie anal 

 fin-ridge, which is .sometimes considerably elevated at 

 this season, as well as along tiie base and in front of 

 the second dorsal fin. 



Tile coloration differs from that of the preceding 

 species in its monotony, being without shar])ly defined 

 spots, and as a ruli- on tlie back steel-l)lue or darker, 

 on the belh' \vliitc, with a silvery lustre on tlie sides 

 of the body. Yet it varies with the age of the fish, 

 the .season of the year, and the locality. In fresh water 

 and with age the back becomes greener, and the belly 

 assumes a muddier tone. The fins are either transparent, 

 grayish white, or, in old .specimens, lirownish. The 

 Prides are entirely destitute of silvery lustre and some- 

 times greenish yellow, sometimes bluish green. Our 

 figures of Prides, as well as of the Lampern, are painted 

 from living S[ieciinens taken by Professor Ketzh'S at 

 Elfkarleby early in October. 



The Lampern is dispersed throughout Europe, 

 Northern Asia, and Japan, as well as the northern re- 

 gions of North America together with Greenland. Theel 

 and TuvBoM brought home Prides of this species from 

 the Yenisei; Gixtheh referred the Fetromyzon japoni- 

 CHS described by Maktens" to the same species as our 

 Lampern; Pefromi/zon plinnhcus {ciharius) and I'etr. au- 

 reus from the ^vest coast of North America have ap- 

 parently no greater claim, judging by the descriptions, 

 to a specific rank; and from Southern Greenland, ac- 

 cording to LCtken, the ]\Iuseum of Copenhagen has re- 

 ceived two specimens of Pctninu/zoii fiuriafiUs. Through- 

 out Sweden this species occurs in both varieties, but 

 seems to be less common in the west than in the ea.st, 

 besides which it has long been known that the more 

 typical form is commonest and largest in the Baltic and 

 the rivers of Northern Sweden. In Norway the last- 



iiKMitioned form, according to Collett, is very rare and 

 has been met with only in Christiania Fjord, but I'efro- 

 nii/soii I'ldiicri is said to be cduinion enough south of 

 the DoNTefjeld, where it attains, according to Kascu, a 

 length of at least 8 dm. Ncu'th of the Dovrefjeld the 

 species has not been found; but Mela adduces it from 

 Varanger Fjord, and it has long been known from the 

 ^^'llite Sea and the rivers of Northern Russia. In Den- 

 mark it has been met with both on the islands and in 

 .Intlaiid. In the Sound it is no rarit\'. ( >n ISornlioliii, 

 according to Feddkusek, only the smaller form has been 

 found. In llussia, (lermany, the Netherlands, Southern 

 Europe'', and the British Islands it is as common as in 

 Scandinavia, in some places perhajis commoner. Ac- 

 cording to Fatiii it is unable to pass the great falls of 

 the Rhine and Rhone, being wanting both in Lake Con- 

 stance and the Lake of Geneva. In Scandinavia, on 

 the other hand, each of the forms occurs both in Lake 

 \A'ener, above TrollhiUtan, and in Lake Wetter. Nearest 

 the sources of the brooks and in small collections of 

 water the smaller form has its home; the larger keeps 

 to the lower courses of the rivers and, in the lakes, 

 to the outlets of the brooks. How high the Lampern 

 ascends in the mountain regions of Scandinavia, is 

 scarcely known as yet. C)lsson'' says that both Lam- 

 perns and Prides are coninion in the southern part of 

 Stroms Vattudal (Jemtland), though they do not ascend 

 the streams flowing thither. According to Tuybom" 

 Prides 11 — lo cm. long have been found at Asele 

 (Angerman Elf, f>4° 10' N. lat.; 300 m. above the sea- 

 level), on flax placed in the river to steep; and similar 

 specimens are sometimes taken, it is stated, in Lake 

 Storlogde (Logde Elf). Lilljeborg found Petromyzon 

 Plmieri at Karesuando (Muonio Elf, 68° 25' N. lat.; 320 

 m. above the sea-level). Fatio sets the limit to the 

 ascent of the Lampern in Switzerland at about 600 to 

 700 m. above the level of the sea. 



Tenacious of life and greedy of prey, the Lanntern 

 has the same habits as the preceding species. Its man- 

 ner of life in the sea is hardly known, for it is met 

 with too seldom in salt water. Baltic specimens have 

 been found to have the intestinal canal (stomach and 

 spiral intestine) filled to distension with a pulpy mass, 

 in which we could distinguish in one specimen morsels 



" Wiegin. Arch. XXXIV, p. 3. 



* Not adduced from Greece, however, by Apostolides. 



>■ ('ifvcra. Vet. Akad. Forh. 1876, No. 3, p. 140. 



'' Nurd. Aarsskr. Fisk. 1883, p. 307. 



