NOTES ON TELEOSTEAN OVA AND LARVAE. 15 



the uiyotomes were very distinct, and faint dark pigment was just 

 appearing. Less than twenty-four hours after this a short caudal 

 rudiment had appeared, and the body was beset with both black and 

 yellow pigment cells. In the caudal region yellow predominated, 

 covering the dorsal surface almost entirely, while of black there were 

 only a few round chromatophores. Over the yolk-sac there were 

 many black and yellow chromatophores stellate and cruciform in 

 shape, and the pellicle of the oil-globule was covered with large black 

 dendritic chromatophores, each with many ramifying rays. The rudi- 

 mentary pectoral fins occurred as relatively large flap-like outgrowths. 

 On the fourth day, when the embryo had wholly surrounded the yolk, 

 yellow pigment had increased in intensity, especially in the post-anal 

 part, and had appeared on the pectoral fins. Black dendritic and 

 pectinate pigment patches, together with yellow pigment, were visible 

 on the embryonic fin membrane. The otocysts were relatively small, 

 and situated so that the distance from the posterior edge of the eye to 

 the posterior edge of the otocyst was equal to the diameter of the eye. 

 The oil-globule had shrunk to a diameter of 0"20 mm. The egg -died 

 before hatching. 



On the 8th July another egg of 1'28 mm. diameter and oil-globule 

 0'215 mm. was taken a short distance south of the Breakwater. The 

 embryonic character as to pigmentation, etc., was quite similar to the 

 above-mentioned, and fortunately this proved to be more healthy. On 

 the 12th the larva was found to have hatched out and was then prob- 

 ably over twenty-four hours old, the yolk being partially absorbed. 

 Its length was 4*5 mm., the distance from snout to anus being 1-7 mm. 

 At this stage it has a general resemblance to a Zeugopterus larva, but 

 the body is less elongate, the anus relatively nearer to the yolk-sac, 

 and the well-developed and richly pigmented pectoral fins especially 

 characterize it as Trigla. There is no well-defined " snout " and the 

 frontal region is peculiarly square. The bean-shaped otocysts, with 

 two very small otoliths, are placed immediately behind the eye. The 

 oil-globule is situated at the posterior end of the yolk-sac, between 

 which and the anus there is a short but deep pre-anal fin. The rectum 

 lies at right angles to the longitudinal axis. Dorsal to the gut above 

 the middle of the yolk-sac is a conspicuous spherical swim-bladder. 

 The pigment is bright canary-yellow and black. The whole of the 

 head, except the eyes, is diffusely covered with yellow. In the eye 

 black is beginning to appear. A continuous dorsal series of rather 

 diffuse yellow chromatophores runs back from the head to a point 

 about I'l mm. from the posterior extremity, beyond which both 

 marginal fins and body are (^uito unpigmented; A similar but less 



