On the Development of the Food-Fishes. 443 indicutes some uncertainty on the subject, and my own expe-rience of the species has now led me to conchide that what has been described as the poor-or power-cod [Gad as mi nut us) by several authors is only the young of the bib. Considerable change occurs in the outline of the tins as the adult condition is reached, and the pigment is also increased ; but a large series from various parts of the British seas leaves little doubt as to the identity of the two forms. It would appear that the confusion in regard to this species has partly arisen from an examination of preserved specimens. This is probably one of the reasons why they are separated in Dr. Giinther's valuable and laborious Catalogue of the Fishes in the British Museum*. It is remarkable that very few males were procured last season, and this out of a large number of examples obtained for examination at the marine laboratory. XLII. — Early Stages in the Development of the Food-Fishes. By Edward E. Puince, St. Andrews Marine Laboratoryt. During the spring and summer of last year (1885) tlie ova of about twenty species of shore and deep-sea Teleosteans were studied in the Marine Laboratory, St. Andrews. Of these about half were carried through the embryonic stages in the tanks of the laboratory, and several species liave, for the first time, been studied and the embryos reared at St. Ancfrews. Six of the species referred to have claimed special attention on account of their economic importance, and the following observations refer mainly to these, viz. : — Gadus merlangiis^ Gadus ceglefnuSj Gadus morrhua, Trigla gurnardaSj Pleuro-tiectes flesus, and Pleuronectes limanda. So far as investigations at present show, this remarkable fact has been established — that, with the notable exception of the herring, the ova of those marine fishes which are of chief commercial value are pelagic, and when mature present almost identical features in structure and appearance. In the course of development likewise few points of dissimilarity appear ; but the warning expressed by Prof. Ray Lankester is none the less just, that each form should be investigated in detail, for " in embryology the practical lesson is daily being more * Vul. iv. pp. 335, 33G (18G2). t Communicated by the Author, having been read at the Aberdeen Meeting of the liritish Association (Section D), September 1885.
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