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Part III. — Thirteenth Annual Report 



rectal process, and some bad appeared around the oil-globule and at the 

 throat and cardiac region. The two brownish bars (dorsal and ventral) 

 at the tail had a somewhat triangular or bluntly conical form, and 

 extended from the trunk nearly to the border of the marginal fin. A slight 

 patch also occurred in the dorsal marginal fin about midway between the 

 caudal bar and the head. The reddish pigment at the rectum passed 

 downward to the termination of the gut, and abruptly ceased, a pale 

 strand of tissue being continued from it to the edge of the marginal fin. 

 The heart lies somewhat low in the'sub-opercular region, which is deeply 

 pigmented. The finely ramified black chromatophores covered the entire 

 region tinted reddish, so that only the middle of the yolk was translucent, 

 and even on this were a few finely branched red corpuscles. The ventral 

 surface of the yolk, as well as the other parts, had numerous black chroma- 

 tophores. By transmitted light the coloured parts had a fine ruby-red 

 hue. The eyes had a similar brownish hue — a few dark touches, as in the 

 figure, also being present. The otocysts and their two otoliths were 

 difficult to observe, from the abundance of pigment. Even at this stage 

 the larval fishes darted about at intervals, resting on the bottom, or 

 floating with the yolk-sac uppermost and the tail inferior. 



After two days, the changes in the larval turbot were — the increase of 

 pigment in the eyes, which were now slightly iridescent. The black 

 chromatophores over the body were more abundant. The bars behind 

 the vent were broader, especially the superior, which almost touched the 

 margiu of the fin. The mouth was open, and the mandible protruded 

 (PI. VIII. fig. 12). The oil-globule adhered to the remnant of the yolk 

 nearly in the middle of the abdomen. Since the 29th June, the oil- 

 globule has occupied various positions in different examples, in some 

 having moved upward and backward with the yolk. 



On the 1st of July, the larval turbot evinced greater activity — darting 

 through the water at intervals, and again resting on the bottom. The 

 increase in the black pigment renders the body dusky brown. The two 

 posterior brownish bars have spread outward, and finely ramified black 

 pigment exists in both. The mid-dorsal patch now touches the body- 

 line, and also presents a few black chromatophores. The same hue tints 

 the marginal ridge over the head and the front of the snout. The black 

 pigment renders both dorsal and ventral surfaces dark when viewed on 

 edge, two long, blackish bands occurring dorsally — separated by the 

 brownish area in the mid-dorsal line. The skin is finely dotted with 

 minute vesicles. The eyes have a greenish iridescent lustre. The 

 marginal fin continues as a prominent border over the vertex to the 

 tip of the snout (Plate VIII. fig. 13). This fin is still propor- 

 tionally broad, though the body has lengthened to fully 3'46 mm. No 

 fin-rays are yet visible in the caudal expansion. Movements of the 

 mandible and hyoidean apparatus occur occasionally. The pectoral 

 fins have considerably increased in size, and are used in balancing. The 

 clavicular bar is also evident. The oil-globule is difficult to see, but in 

 diminished size it is still present with the remnant of yolk — in some 

 near the lower border of the abdomen. A feature of moment in these 

 larval turbot is their hardihood, for after exposure on a slide in a few drops 

 of water for two hours they survived, and became active when transferred 

 to their vessel. 



The yolk was entirely absorbed on the 3rd July — that is, about the 

 7th day. The marginal fin over the head has increased in depth, 

 and the black and other pigments have ramified outward in all directions 

 at its inner border. The caudal expansion now shows embryonic rays, 

 which, however, are very faint. Blood-vessels with pale blood are now 

 observed at various points, e.g., the sub-intestinal coursing upward in 



