SMALL LAMPREY. 197 



morphosis. The larval form, under the name of Ammocafcs (Dumeril, Cuv., A'. An), was 

 long considered to be a species distinct from the Pcl)-oinyzon plancri, until Muller (Miiller's 

 Arcliiv., 1856, p. 325) succeeded In tracing the development of Amviocatcs hmnchialis into 

 P. plaucri. It is probable, therefore, that not only the fishes of the genus Pcfromyzoii, but 

 also those of allied genera pass through a similar metamorphosis. In the larval form, the 

 general shape of the body differs in no important respect from the mature individual ; but 

 the upper lip Is semicircular, and the lower lip is very small ; there are no teeth, and the 

 mouth Is furnished \yith numerous short membranous cirri. The eyes are very small, and 

 are situated at the bottom of a small deep depression or groove. Ammoccetes branchialis is 

 said to require three or four years for its complete development. The term Atmnocates, or 

 "sand-dweller," refers to the habits of this little larval form hiding itself in the sand or mud, 

 for owing to the Immature horse-shoe structure of the mouth. It is unable to adhere to stones 

 or other submerged bodies, as in the case of the adult forms. The term hmnchialis was 

 bestowed upon this fish by Linnaeus, from a notion that It attached itself to the gills of 

 fishes. As to size, it seldom exceeds six or seven Inches in length, and is about as thick 

 as a goose-quill. The fishermen use these fish as a bait in ivhiffing for Pollacks. "Burled 

 in scattered companies In the soft soil," writes Couch, "It may be said to lead the life of 

 the mole; and It is there It finds all it wants of food, in search of which, by taste or 

 scent. It moves through its tracks as appetite or disposition prompts ; and from observation 

 it may be judged that, except in search of new feeding ground, it never willingly exposes 

 itself to the dangers of a rapid stream, the strength of which It might scarcely be able to 

 stem, or to the appetite of any prowling inhabitant of the river, from which its powers would 

 not enable it to escape." Mr. Couch succeeded in keeping specimens of this larval form for 

 months alive in stagnant water, with mud at the bottom, without injur)^ to its health or 

 activity. Dr. Plot, In his History of Oxfordshire, calls this Lampern the Pride of the Isis; 

 the term prid, or pride, is probably a form of the fuller word Lam-/;rr, from which by a 

 process of phonetic decay it appears to have been derived.* 



In the mature form of this species the mouth Is circular, and provided with numerous 

 papillae forming a fringe, — hence called " The Fringe-lipped Lampern " by some authors, — the 

 two dorsal fins are In close connexion, but separated by a deep notch; the dentition differs 

 from that of P. fluviatilis merely In having the cusps less prominent and more obtuse. It 

 grows to the length of eight or nine inches. This species is widely distributed, occurring in 

 the rivers of Europe and North America. The spawning time is in March and April. This 

 species was named by Bloch after Planer, a Professor at Erfurt. In colour P. branchialis 

 hardly differs from P. Jluviatilis. I find this species common in the brooks and streams of 

 various parts of Shropshire. Excepting as bait or food for other fish it has no value. 



* "Pride, a Mud Lamprey. West. 'Lumbrici are littell fyshes taken in small ryvers, whiche are lyke to lampurnes, 

 but they be muche lesse, and somewhat yeolowe, and are called in Wilshyre prides,'' (Elyote's Dictionarie, fol. Lond. 

 1599." — Halliwell's Arch. Diet. p. 645.) 



