The post-larval blennies taken off Plymouth during recent years have been assigned to three species, namely, Blennius ocellaris L., Bl. pholis L., and Bl. gattorugine L. The process of identification, however, has emphasised the need for the revision of the available descriptions and illustrations of the various stages in development, and I have, therefore, thought it desirable to report on the Plymouth forms and give drawings of them.

Blennius Ocellaris (12 rays to the pectorals).

Ehrenbaum (2, p. 83) has copied two figures of the young of this species which were originally produced by Holt (5, p. 45), and it is somewhat unfortunate that both need to be commented upon. The first is satisfactory as a representation of the appearance of a larva some time after hatching, but the length is wrongly given as 6.3 mm. Garstang (4, p. 74) explained that this was an error in transcription, and, after a re-examination of Holt's specimens, he found that the total length was 4.6 mm. (varying between 4.55 and 4.65). The second figure, depicting a young fish of 18 mm., which Holt tentatively assigned to Bl. ocellaris, was taken exception to by Garstang and the identification questioned, and it must be admitted that it does not portray satisfactorily the characters of the species.

The full account of the rearing of the young from the egg by Garstang (4) was unfortunately not illustrated; but as several of his original specimens are in the Plymouth collection, I have been able to identify quite readily the more recently captured examples and have made a series of drawings which are given below (Figs. 1 to 4).