. Bulletin of the British Museum (Natural History) Zoology. 90 GORDON J. HOWES. Fig. 16 Hyoid arch elements of; A & B, Macruronus magellanicus (BMNH : 342-56), and C, Merluccius merluccius (: 44- 47), alcian-alizarin stained preparations. The hyoid bar in A is shown in medial view, the urohyal in B & C in lateral and (B) dorsal views. and three pharyngobranchials (numbers 1-3). Pharyngo- branchial 1 is cartilaginous; pharyngobranchial 3 bears three struts which articulate with the 2nd, 3rd and 4th epibranchials; pharyngo-branchial 2 articulates with the 1st epibranchi
. Bulletin of the British Museum (Natural History) Zoology. 90 GORDON J. HOWES. Fig. 16 Hyoid arch elements of; A & B, Macruronus magellanicus (BMNH : 342-56), and C, Merluccius merluccius (: 44- 47), alcian-alizarin stained preparations. The hyoid bar in A is shown in medial view, the urohyal in B & C in lateral and (B) dorsal views. and three pharyngobranchials (numbers 1-3). Pharyngo- branchial 1 is cartilaginous; pharyngobranchial 3 bears three struts which articulate with the 2nd, 3rd and 4th epibranchials; pharyngo-branchial 2 articulates with the 1st epibranchial; interarcual cartilage absent. There are 8 slender, denticulate gill-rakers on outer surface of 1st epibranchial and 2 or 3 flat, denticulate rakers on inner surface. Similar rakers occur on 3rd and 4th epibranchials. Tooth patches are present on 3rd epibranchial and pharyngobranchials 2 and 3. In Merluccius epibranchial uncinate processes are lower than in Macruronus and the struts of pharyngobranchial 3 are longer and prominently curved mesad. Inada (1981) and Patterson & Rosen (1989) report pharyngobranchial 1, but there is no interarcual cartilage. Tooth patches are present on pharyngobranchial 2 and 3 and on 3rd epibranchial. Epibranchial 1 bears 0-3 long gill-rakers on outer margin and two or three short, cylindrical denticulate rakers along inner surface. Pectoral girdle (Fig. 19) Principal differences between pectoral girdle elements of Macruronus and Merluccius are in the cleithrum, which in the former lacks the prominent dorsoposterior process of the latter (Inada, 1981:85; fig. 38); coracoid, which in Macruronus has a relatively short anteroventral process; and postcleithrum, which is longer and more deeply curved than in Merluccius with an arrow- as opposed to a club-shaped head (Inada, 1981; figs 39, 40). Pelvic girdle (Fig. 20) Noticeable differences occur in pelvic bone shape between Macruronus and Merluccius. In Macruronus, pelvic bone elongate with stron
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