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Show 1894.] TELEOSTEAN MORPHOLOGY. 417 The fin-ray formula is enumerated by Lilljeborg as follows :- Di. 13-14. Dn. 78-85. A. 75-80. Pelv. 5-6. The examples before m e give Di. 12-15. D u . 69-75. A. 70-74. Pelv. 6-7.1 The difference in the number of rays in the second dorsal and anal is considerable, but the small number of m y specimens and the absence of any information as to the number represented in Lilljeborg's formula render it impossible to say whether such difference is indicative of local variation, or depends on nothing more important than chance. Description of the Specimens. I append a table of dimensions, since such facts are often of more importance in the eyes of an ichthyologist than an author's deductions therefrom. The specimens A to E are those from Faroe, and the measurements were taken from the fresh condition; the Iceland examples, x and y, were measured after preservation in alcohol. The anterior extremity as here denoted is the extremity of the lower jaw when the mouth is closed. The measurements are given in inches. Specimen A Total length Total length without caudal... Length of head Preorbital length Horizontal diameter of eye ... Vertical diameter of eye Width of interorbital space... Greatest height of body Greatest girth of body Height of caudal peduncle ... Ant. extremity to 1st dorsal... Ant. extremity to 2nd dorsal Ant. extremity to anus Length of pectoral , Length of pelvic , Length of barbel , 10* 3| 13± If 14i 18f 22 5 4* 9 B 47 10i »4 2i lily9, H 15 14 13| 17* 22 4* 0 • * ' # 44| 9| if if 5| 15 If 13§ 17| 21 4f 3§ 9 D 46i 45| 9i 34 2 H 1^ 62 132 H 12| E 42 391 8i 3 H If ITV 51 124 H Hi 14! 18 4i 31 _7 8 47 44 9 3 2 1 » 15 z] B oca If 13 17 19 4f 46 t2J 9i i * i 11 ' 5ca 20 4| 3| The lower jaw projects from g to f inch beyond the upper, and the angle of the gape reaches to about a vertical from the centre of the eye. The teeth are not distinguishable either in structure 1 For purposes of comparison I append the fin-ray and vertebral formula of M. vulgaris, taken from Lilljeborg (op. cit. pp. 131 and 137), as dealing with the most Northern examples as to which information is available : - Di. 13-16. Dn. 62-70. A. 57-66. Vert. 64-65. 2 The eversion of the stomach in this specimen renders the value of these measurements uncertain. |