A. branchialis, Flem. Brit. An. p. 164. Blainv. Faun. Franc. p. 3. pl. 2. f. 3, & 4. Petromyzon branchialis, Linn. Syst. Nat. torn. I. p. 394. Bloch, Ichth. pl. 78. f. 2. Turt. Brit. Faun. p. 110. P. csbcus, Couch in Loud. Mag. of Nat. Hist. vol. v.

* Brit An. p. 164.

p. 23. fig. 10. Lampetra caeca, Will. Hist. Pise. p. 107. tab. G. 3. f. 1. Ray, Syn. Pise. p. 36. Pride, Plot, Oxfordsh. p. 187. pl. 10. Penn. Brit Zool. vol. iii. p. 80. pl. 8. no. 29. Id. (Edit. 1812). vol. iii. p. 107. pl. 10. Bowd. Brit. fr. wat. Fish. Draw. no. 32. Lamprillon, Cuv. Reg. An. torn. ii. p. 406.

Length

From six to eight inches.

Description

{Form). Body more slender than in the last genus, vermiform, scarcely larger than a goose-quill, marked with numerous transverse lines, subcylindric anteriorly, somewhat compressed and tapering beyond the vent: jaws and lips soft and membranaceous; the upper lip semicircular, fleshy, prominent: inside of the mouth papillose, with a lingual and palatine plate somewhat harder than the other portions, but no true teeth: eyes obscure: a single nostril on the upper part of the head: branchial orifices seven in number, situate in a kind of lateral groove; the body at this part somewhat dilated: skin naked, and covered with an abundant mucosity: two dorsals; the first small and low; the second closely following, longer, and rather more elevated anteriorly, but sloping off to a narrow edge before uniting to the caudal: fleshy portion of the tail sharp at the extremity, but the fin rounded: vent rather anterior to the commencement of the last quarter of the entire length; anal commencing a little beyond it, uniting with the caudal. Obs. Two distinct forms of this fish are not unfrequent: in one, the eyes are larger, the mouth smaller, the snout more elongated, and the orifice on the crown further removed from the extremity: in the other, the eyes are smaller and very obsolete, the mouth larger, and the snout shorter: whether these are merely sexes, or two different species, is not certain. {Colours.} "Bluish or reddish gray above, whitish beneath; fins of the same colour and almost transparent *." The following are those which Mr. Couch assigns to his Petromyzon cceeus: "Colour dusky yellow, dark on the back, light below; fins light".

Said to be frequent in the rivers near Oxford, particularly the Isis, where it was first observed by Plot. Found also in other parts of England, as well as in Ireland. Buries itself in the soft mud. Has not the power of adhering by the mouth, like the Lamprey; although the lips, according to Mr. Couch, are capable of extensive and complicated motions. Spawns at the end of April or the beginning of May. Probably the Stone Grig of Merrett†.