6098 



Crustacea. 



it. Branchial openings, eight on each side, are placed in a curved groove or canal. 

 (In this respect it differs from all our Petromyzidae, as yet described, so far as I ara 

 aware). The mouth may be said to be squarish, with the under lip depressed. 

 There is no appearance of teeth, but numerous and very delicate cirrhi seem to supply 

 iheir place. When fresh, it was on the top part of a most beautiful oil-green shading, 

 and a dull yellow on the sides and belly: a bright yellow line runs along the middle 

 of the back, beginning about an inch from the head, and extends round the caudal to 

 the belly, dyeing the dorsals of the same colour. From the foregoing it will be at once 

 apparent, that though it agrees in some respects with Ammocaetes branchialis of 

 British authors, still it differs very much in others. The eight branchial apertures 

 and the squarish mouth are two most important distinctions, and cannot, I should 

 think, allow it to be ranked only as a variety of the species just named. But 

 as I have no wish whatever to augment species but on truthful grounds, I leave it to 

 the readers of the ' Zoologist ' to decide, if any of them will be kind enough to give 

 their opinion. — Thomas Edward ; Banff^ April 14, 1858. 



[This description has many points of extreme interest, and I sincerely hope that 

 my ichihyological readers will endeavour to throw some light on the subject. The 

 family PetromyzontidsB is made to comprise four genera, Petromyzon, Amniocaeles, 

 Myxine and Amphioxus: the connexion of the last of these with the other three is 

 not very manifest. Petromyzon and Ammocsetes have seven lateral orifices or gill- 

 openings; in Myxine I believe that two only have been observed. The wonderful 

 history of Myxine appears to me to require further elucidation. It seems incredible, 

 and yet remains uncontradicted, that this worm-like fish should live within the bodies 

 of living cod and haddock, having no other food than the proper substance, the muscle 

 of these fishes, just as the larva of the ichneumon-fly feeds on the viscera or muscle 

 of the living larvae of moths and butterflies. I shall feel sincerely obliged to any 

 naturalist who can, from personal observation, confirm, elucidate, or even refute this 

 apocryphal-looking theory ; as also to any reader who can identify Mr. Edward's 

 description as applicable to any known species of the family PetromyzontidaB. — 

 Edivard Neivman]. 



Descriptions of Two Unrecorded British Isopoda, — During a short trip to 

 Plymouth and Polperro I met with the two following Oniscoids, which have hitherto 

 escaped notice : — 



Philoscia Covcmi^ Kinahan, 



Body smooth. Head rounded, transverse, nearly straight across the front. 

 The third ring produced into a small lobe beneath orbits. Telson (last ring of body) 

 narrow, triangular. Apex obtusely rounded, fringed with four to six stiff spines ; lateral 

 margin distinctly excavated. Appendages of telson having the accessory appendage 

 scarcely one-fourth the length of the ischium, which latter is elongate-subulate. 

 Colour fulvous-gray, with patches of white. Runs with great activity, does 

 not roll. 



Habitat, — Among stones and decaying sea-weed near high tide-mark, at Tallant 

 Cove, Cornwall, where it was in company with Orchestea littorea, Porcellio scaber, 



