NOTES ON TELEOSTEAN OVA AND LARVAE. 7 



1. PELAGIC EGGS. 



Ctciwhiljrus rupcstris, L. Gold-sinny or Eock-wrasse. 



Holt (11a), p. 465, Figs. 23, 24, 28-30. 

 Heincke u. Ehkenbaum (10), p. 266, Fig.l7a-d. 



This species aflbrJed the most numerous of the pelagic eggs taken 

 during the months of May, June, and July. Belonging to a littoral 

 species it was taken for the most part in near-shore tow-nettings, and was 

 practically absent from the offshore Eddystone Grounds ; but there was 

 one notable exception to this on July 20th, when several were taken one 

 and a half miles south-east of the Eddystone. The egg, which is 

 easily recognized by its small size, clear homogeneous yolk devoid of 

 an oil-globule, small perivitelline space, and embryo with slender body 

 and uniformly distributed pigment, has been described by Holt 

 {op. cit.) from the south-west coast of Ireland and from the Gulf of 

 Marseilles, and by Heincke and Ehrenbaum from Heligoland. The 

 size of the egg is liable to much variation. The diameters recorded for 

 the North Sea are 0-72 to 094 mm., for the Mediterranean 0-70 to 

 0-83 mm., and for the Irish coast 0"8o5 mm. The diameter of my 

 eggs ranged from 78 to 090 mm., averaging "878 in IMay, "839 in 

 June, and "822 in July. The first specimen was taken on the 7th of 

 May, the last on the 20th of July. The newly hatched larva has a 

 total length of 2'16 mm., the distance from snout to anus being 

 1"22 mm. 



The post-larval stages have been taken in the young-fish trawl from late 

 June onward, but they do not appear in that relative abundance which 

 one might expect from the commonness of the ova. This is probably 

 due to the fact that they early seek the environment of inshore rocks, 

 whicli is the habitat of the adult. Holt (lid, p. 125) speaks of 

 young examples being common on the zostera beds of Cawsand Bay 

 and the Yealra estuary, but judging from his later publication of a 

 drawing of a young wrasse taken at Fowey (Marseilles, 1899), and 

 erroneously identified as C. nqjesti-is, it is probable that at this time he 

 was confusing this species with another wrasse, probably L. maculatus, 

 the young of which are more commonly met with off the shores of 

 this neighbourhood in summer. The later post-larval stages, like the 

 early larva, are characterized l)y their lack of black pigment, which is 

 limited to a large spot at the base of the posterior end of the anal 

 fin and at the base of the caudal fin, and for the rest a little in the 

 peritoneum, on the head and on the throat. 



