272 Part III. — Twenty-second Annual Report 



row of similar pigment corpuscles. The eyes are black. The post-anal 

 region is marked by three main transverse bars of cbromatophores ; they 

 are equi distant from one another. Each bar consists of a dorsal and a 

 ventral moiety. The hindmost is in the region of the future caudal fin, 

 and is large. Between the bars there are three pigment groups situated 

 ventrally on the edge of the muscle-segments ; they may be termed secon- 

 dary groups, in contradistinction to the main broad bars. Of the post-anal 

 pigment groups just mentioned, the hind main bar alone extends on to the 

 marginal fin. Only one pigment spot was, in addition, found on the 

 marginal fin ; it was situated on the ventral fin. A ventral view of this 

 post-larva is shown in Fig. lb. 



In Fig. 2 a specimen similar in size to one of those described by Kyle 

 is reproduced. It measures 12"5mm. in length, and in greatest iDreadth 

 reaches about 3mm. A greater amount of pigment is found in this 

 individual than in the preceding. Along the ventral edge of the muscle- 

 segments in the post-anal region a few more intermediate or secondary 

 pigment spots are seen, and some pigment was made out on the ventral 

 marginal fin in large and small spots. Anterior to the anus the condition 

 of the preceding specimen holds. The caudal pigment is now diffuse ; 

 the caudal fin-rays are being laid down and the tail region is becoming 

 heterocercal. The rudiments of the interspinous bones are indicated by a 

 somewhat opaque part of the marginal fin, next the muscle-segments. 



The interspinous hones, still very small, are to be made out in the next 

 figure (3), a drawing of a post-larva mea.suring 14mm. in length and 

 5mm. in greatest breadth. In this specimen the large pigment corpuscles 

 on the hind part of the optic lobes were prominent. A natural-size 

 sketch of this post-larva is given in Fig. 9. 



A witch 18mm. in length is reproduced in Fig. 4. The fin-rays are 

 now almost completely formed, and the tail is nearly homocercal 

 in character. A row of small pigment spots along the junction of the 

 ventral interspinous bones and the fin-rays is made out. 



In Fig. 5 all the interspinous bones and the fin-rays are formed. This 

 example is of the same size as the specimen recorded by Holt and Byrne. 

 In length it measures 25mm., in greatest breadth it reaches 7'5mm. 

 The fin-ray formula is — Dorsal, about 110 : Anal, about 95 ; Caudal, 22. 



Fig. 7a is an enlarged drawing of a witch measuring 34mm. In it 

 the pigment was not very prominent ; it had probably faded. 



A post-larval form, measuring 38mm., is shown in Fig. 12. Trans- 

 formation is not yet completed. A drawing of the left side of the head 

 of this example appears in Fig. 8. 



A completely metamorphosed witch, measuring 44mn)., is reproduced 

 in Fig. 13. Holt described one which was a little smaller, viz. 42mm. 



The migration of the left eye to the right side of the fish is a slow 

 process. In the fish measuring 25mm. it has moved to a noticeable 

 extent. It then appears a little above the ridge, when the fish is viewed 

 from the right side (Fig. 5). In the large post-larva, 38mm. (Fig. 12), 

 the eye is on the ridge ; in another, measuring 40mm., the migration was 

 not completed (Figs. 6a and 6b). 



Dr. Fulton examined the last-mentioned specimen (40mm. long) 

 shortly after it was killed in formaline. He found that the only pigment 

 then visible was black. It was distributed as follows: — On the snout 

 and jaw there was a collection of little specks ; on the front of the lower 

 jaw a like collection. A group of spots was present on the optic lobes, 

 while a broad band of spots was conspicuous on the hind part of the 

 abdomen. On the median line there were, on the post-anal body, six 

 equi-distant pigment patches. The dorsal interspinous region showed 

 eight fainter patches, while five or six similar patches were seen on the 

 ventral interspinous region. 



