OCR Text |
Show 232 MR. G. A. BOULENGER ON [Apr. 7, Mrs. Eigenmann1 has induced me to make a thorough re-examination of the Siluroids collected by those gentlemen, the more so as Dr. Hensel's account2 is much in need of revision. 1. PIMELODUS (PIMELODELLA) LATERISTRIGA, Miill. & Trosch.3 2. PIMELODUS (PIMELODELLA) NIGRIBARBIS. (Plate XXV. fig. 1.) Pimelodus (Pseudorhamdia) nigribarbis, Bouleng. Ann. & Mag. N . H . (6) iv. 1889, p. 2C6. D. 1/6. A. 17. P. 1/8. Head bony above, granulated, once and two thirds to once and four fifths as long as broad ; occipital process obtusely keeled, twice as long as broad, in contact with the basal bone of the dorsal spine; length of head thrice and a half to thrice and two thirds in the total (without caudal) ; eye rather large, its diameter four and a half times in the length of the head, once and a half in the length of the snout, twice in the interorbital space ; maxillary barbel extending to the origin of the anal, outer mandibular to the extremity of the pectoral. Praemaxillary teeth present, but very feebly developed. Pectoral spine a little longer than dorsal, three fourths the length of the head, serrated on both sides. Dorsal fin much deeper than long, the spine strong, but little shorter than the anterior branched rays, two thirds the length of the head; adipose fin one sixth to one eighth of the total length (without caudal), two thirds to one half of its distance from the dorsal. Depth of body about one fifth of the total length. Caudal deeply forked, with the lobes pointed, the upper being the longer. Upper parts and fins powdered with black, most closely on the ventrals and anal and on the barbels, which are almost black. Total length 155 millim. I have now before m e three specimens, from the Camaquam4 or Icamaquam River. They differ from the description of Pimelodus valenciennis, Liitk., in the width of the head being more instead of less than half the length, and in the larger eye, the diameter of which is contained four and a half times instead of six times in the length of the head. 1 Occasional Papers of the Calif. Acad, of Sc. i. 1S90. 2 Arch. f. Nat. 1868 & 1870. 3 1 have compared m y specimens with one from the Rio das Velhas, described by Prof. Liitken, and received from the Copenhagen Museum. I have seized this opportunity to re-examine m y P. bucklcyi and compare it with a specimen from Macacos recently received from the Museum of Comparative Zoology under the name of P. buckleyi. In the types tbe pectoral spine is as long as the distance from the anterior border of the eye to the opercular border aud practically smooth on its inner edge; in the specimen from Macacos the pectoral spine is stronger, as long as the distance between the base of the maxillary barbel and the opercular border, and its inner edge is distinctly though very feebly serrated. There can be no doubt that the two are distinct, and I venture to propose for the species described by Dr. and Mrs. Eigenmann as P. bucklcyi the name of Pimelodus {Pimelodella) e/yenntanni. 4 Not Camapuam, as stated by mistake in the original description. |