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Part III. — Seventeenth Annual Report 



the pigment on the sides and abdomen, instead of consisting of minute 

 black spots, is in the form of large dark brown stellate corpuscles, giving 

 the little fish an almost black colouration. This difference in pigmenta- 

 tion may, however, be of no importance, since in life the minute spots in 

 the other specimens would no doubt be stellate. It may perhaps be 

 sufficiently explained by the assumption that in one case the corpuscles 

 remained expanded after death, while in the other they contracted. The 

 largest specimen of the series — viz., one ll*5mm. — is damaged (fig. 12). 

 Each example, with the exception of 1 and 2, had very characteristic 

 teeth. In Fig. 7 two long recurved teeth were present in front in the 

 lower jaw, one on each side of the symphysis of the mandible. Behind 

 these on each side were two triangular teeth. In the upper jaw three 

 teeth, similar to those of the lower jaw, were found on each side. The 

 front tooth, recurved like that on the mandible, was not quite so 

 prominent as the latter. The smallest form in which the teeth were 

 noticed was Fig. 3, where the two recurved teeth and one or two 

 triangular teeth were present. The blunt shape of the head is a feature 

 of note in this species. The only young forms hitherto described that 

 resemble the above are the young mackerel sketched by Holt.* From the 

 general resemblance between my specimens and those recorded by Holt, 

 as regards general form, arrangement of the fins, and the possession of 

 teeth, I am convinced that the fishes I have described above are the 

 young of the mackerel (Scomber scombrus). A larval mackerel was 

 captured on Station V. on 7th July. It exactly resembles the larval 

 mackerel described by Cunningham.t 



Lvpadogaster bimaculatus was frequently met with in the tow-nets. 

 The most noticeable points in this form are the truncated head, and the 

 pigment, which is uniformly scattered over the body, with the exception 

 of the posterior third of the tail and the top of the head. In the smaller 

 examples — e.g., fig. 8b, figs. 9 and 10 — the head is quite free of pigment. 

 In the largest specimen sketched — viz., fig. 11 — the pigment has begun to 

 appear on the top of the head. The pigment from either side of the 

 abdomen extends downwards and forwards, meeting in the hyoid region. A 

 V-shaped arrangement is then given to the pigment on the under surface of 

 the head (figs. 8c and 11c). The above specimens do not show the sucker. 

 In older examples — viz., of a length of 10mm. — the sucker is well developed, 

 and in one at 8mm. it is seen indistinctly. The latter also shows the V- 

 shaped arrangement of pigment in the hyoid region. The pigment in 

 those from 7*5-10mm. long is, as described by M'Intosh and Master- 

 man, J laid down in four more or less regular longitudinal rows of large cor- 

 puscles on the side of the body. A semicircular curve of pigment follows 

 the outline of the mid-brain. No other pigment is present on the head. In 

 an example of 5mm. length the pigment consisted of large chromatophores, 

 instead of minute spots as in those sketched. It is probable that those post- 

 larval forms which were put into the preserving fluid when alive retain 

 their chromatophores in an extended condition, while those which were 

 killed in the net exhibit a pigmentation consisting of minute spots. The 

 bulging eyes were characteristic of all the examples. The short stumpy 

 pectorals were well seen in -specimens from 5mm. upwards. In the 

 specimen 10mm. in length, the V-shaped arrangement of pigment in the 

 hyoid region was absent. The larva of this species has been described 

 by Holt,§ 



* Jour. Mar. Biol. Assoc., vol. v.. No. 2. 

 (- Op. ext. 

 % Op . cit. 



§ Scientific Trans. Roy Dublin Uoc, yil, I., 1891, p. 447. 



