522 PISCES (CARTILAG.) CYCLOSTOMI. [PETROMYZON. 



to the Dutch to be used as bait in the Cod-fisheries. Food, according 

 to Bloch, insects, worms, small fish, and the flesh of dead fish. Spawns 

 towards the end of April or beginning of May. Sometimes called a 

 Lampern. 



211. P. Planer^ Cuv. (Planer's Lamprey,) Dusky 

 blue above, silvery beneath : dorsals contiguous. 



P. Planeri, Cuv. Reg. An. torn. n. p. 404. Nilss. Prod. Ichth. 

 Scand. p. 122. Lampetra parva et fluviatilis, Will. Hist. Pise. 

 p. 104. tab. G. 2. f. 1.? 



LENGTH. From eight to ten inches. 



DESCRIPT. Differs from the P. fluviatilis, principally in having the 

 two dorsals contiguous, or with only a very small space between: the 

 first commences at about, or a little before, the middle of the entire 

 length ; the second at exactly two-thirds of the same : the vent is, 

 relatively, a little further from the extremity of the tail; the body is 

 also somewhat thicker in proportion to its length. In all other respects, 

 including colours, armature of the mouth, &c., the two species are 

 identical. 



This species is evidently the P. Planeri of Cuvier and Nilsson, but 

 not of Bloch and Blainville. That of Bloch, Cuvier thinks is only the 

 young of P. fluviatilis. It is probably also the species described by 

 Willughby under the name of Lampetra parva, in which he expressly 

 speaks of the two dorsals being contiguous. Willughby, however, erro- 

 neously considered it as the Pride of Plot, a circumstance which has led 

 to some little confusion in the works of later authors with respect to the 

 synonyms of this last fish. Whether the P. Planeri be common in this 

 country I am not aware. My specimens were given to me by Mr. Yarrell, 

 who obtained them from a brook in Surrey. The same gentleman has 

 since received it from the Tweed. 



(47.) P. Jurce, Mac Cull. West. Isl. vol. n. pp. 186, 187. pi. 29. 



Under the above name, Dr. Mac Culloch has described a species of 

 Petromyzon, which he considers distinct from those hitherto noticed by 

 naturalists. He observes that " in size it approaches to the P. fluviatilis, 

 which it also resembles in the proportion and disposition of the fins ; but 

 that it differs materially in the absence of the annuli, in the greater number 

 of the teeth, and in the number and forms of the bony bodies which sur- 

 round the opening of the throat." This fish was found adhering to the 

 back of a gray gurnard on the Eastern shore of Jura : the specimen was 

 not preserved. Dr. Fleming does not seem to allow that it is specifically 

 different from the P. fluviatilis*, an opinion in which I feel inclined to 

 join. 



GEN. 78. AMMOCCETES, Dumtr. 



212. A. branchialis, Flem. (Pride.) 



A. branchialis, Flem. Brit. An. p. 164. Blainv. Faun. Franc,. 

 p. 3. pi. 2. f. 3, & 4. Petromyzon branchialis, Linn. Syst. Nat. 

 torn. I. p. 394. Block, Ichth. pi. 78. f. 2. Turt. Brit. Faun. 

 p. 110. P. C8BCUS, Couch in Loud. Mag. of Nat. Hist. vol. v. 



* Brit. An. p. 164. 



