. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. Figure 2. Distribution of laterosensory pores in a generalized galaxiid. A, Lateral head; B, Dorsal head. Northern Hemisphere pikes (family Esoci- dae), probably because of the extremely posterior position of the dorsal and anal fins and the long jawed appearance of the single species with which they were ac- quainted. However, these similarities are superficial. The fishes in the family are scaleless, with thick, highly mucigerous, leathery skins. The head is usually moder- ately large, with prominent jaws, the upper
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. Figure 2. Distribution of laterosensory pores in a generalized galaxiid. A, Lateral head; B, Dorsal head. Northern Hemisphere pikes (family Esoci- dae), probably because of the extremely posterior position of the dorsal and anal fins and the long jawed appearance of the single species with which they were ac- quainted. However, these similarities are superficial. The fishes in the family are scaleless, with thick, highly mucigerous, leathery skins. The head is usually moder- ately large, with prominent jaws, the upper and lower varying in proportional develop- ment so that the lower may protrude, recede, or be equal in length to the upper. Lateral line pores on the head are well developed. In New Zealand representa- tives, the disposition of these pores is fairly constant, with only occasional individual variations in pore number (Fig. 2). Then- disposition can be related to the supra- orbital, infra-orbital, and hyomandibular branches of the lateral line system of the head (see Lagler et al., 1962: 391). The lateral line is well developed on the trunk from the upper edge of the opercular aperture to the middle of the tail base. It consists of a series of superficial papillae, set in a midlateral furrow, which may be well defined, especially caudally. In some species groups there is a dorsal accessory lateral line along the dorsolateral trunk, evident as a more or less distinct linear series of small, widely-separated papillae from the occiput to about the dorsal fin. The nostrils are well developed, the anterior one set in a small depression and tubular. In Neochanna it is especially well developed, sometimes extending forward beyond the upper lip. The posterior nostril is a simple aperture. The form of the mouth varies, the profile of the jaws from the ventral aspect varying from deep and narrow, U-shaped, to broad and shallow, with depth much less than breadth (Fig. 3). In the adults of
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