456 PHYSOSTOMI. 



B. Teeth in luthjaM:!!, vilh'fonn or cardiform. 



1. Rita hastata, Plate CIII, fig. 4. 



Arlus hastatus, Val. in Jacq. Voy. Ind. Ori. Atl. Poiss. pi. 18, f. 2 ; Cuv. and Val. sv, p. 97. 



Arius pumilus, Val. 1. c. f. 1 (young). 



Fhractocephalus Jeuturnee, Sykcs, Trans. Z. S. ii, p. 372, t. 6.5, f. 3. 



Ttdgrua ? Jeuturnee, Jerdon, M. J. L. and Sc. 1849, p. 340. 



B/ita luistata, Giinther, Catal. v, p. 93. 



Hita Jeuturnee, Giinther, Catal. v, p. 93. 



B. viii, D. i I 0, P. 1/10, V. 7-8, A. 13-14 (^=^), C. 17. 



Length of head 4| to 4f, of caudal 5 to 6, height of body 6 in the total length. Eyes— coxered with 

 skin, pupil oval, diameter.? 4j to 5 in the length of head, 1^ diameters from the end cf snout, and 1 apart. 

 Greatest width of the head equals its length behind the angle of the mouth : upper jaw the longer : 

 the width of the mouth 3/8 of the length of the head. Upper surface of the head (except just anterior to the 

 occipital process) covered with skin, the portion in front of the occipital process and the process itself 

 M-ith roughened lines, the latter half longer than wide at its base, anteriorly emarginate to receive the basal 

 bone of the dorsal fin. Scapular process rough but not elongated. Cubito-humeral process as long as the head, 

 sharply pointed posteriorly, and rugose in lines. Barhels — the maxillary reach the base of the pectoral 

 fin, the mandibular to below the hind edge of the eye : the nasal ones short. TeetJi — in villiform or cardiform 

 i-ows in both jaws : in two elliptical patches on the palate, converging anteriorly, and widely asunder along the 

 median line, they consist of pointed ones anteriorly and more granular ones behind. Fins — dorsal spine of 

 moderate strength, as long as, or even longer than, the head, finely serrated posteriorly in its upper portion, 

 and also anteriorly along its lower third : length of the base of the adipose dorsal 2/3 of that of the rayed fin : 

 pectoral spine stronger and a little longer than that of the dorsal, denticulated on both edges : caudal 

 forked. Colours — brownish along the back, silvery on the sides. 



The type specimen of A. Jmstatus, Val. is about 41 inches in length and may have come from Poena 

 ■where it is common, it has villiform teeth in the jaws. 



Habitat. — Deccan, Poona, Tamboodi-a and Kistna rivers. 



Genus, 5 — Arius, Cuvier and Yalenciennes. 



Sciades, sp. and Ariodes, MiiU. and Trosch. : HexanematicJdJiys, Guiritinga, Eemiarius, CcpJialocassis, 

 Ketuma and Pseudarius, Bleeker. 



BrancJdostegals from five to six. GiU-memhranes not confluent witJi tJie sJcin of tJie istlimus, and scarcely, or 

 vot noteJied. Head osseous sujieriorly, or covered with very tliin sJcia. Eyes witJi free orbital margins. MoutJt, 

 anterior : upper jaw generally tJie longer. Anterior and posterior nostrils placed close togetJier, tJie latter being 

 provided ivitJi a valve. Barbels six, one maxillary, and two mandibular pairs. TeetJi in tJie jaws villiform : tliere 

 are nearly* always palatine, and sometimes vomerine ones, tJiese may be villiform or granular. First dorsal witJi 

 one spine and seven rays .-f tJie adipose of moderate lengtJi or sJiort : pjectoral spine strong and serrated : ventral witJi 

 six rays, situated beJiind tJie vertical from tJie posterior margin of the rayed dorsal fin : caudal forked or emarginate. 

 An axillary pore. Air-vessel not enclosed in bone. 



Considerable stress has been laid in this genns upon the character of the teeth, and whether tliey are 

 villiform or granular forms a good method of division. Further sub-divisions, as whether the groups are 

 continuous or not so, appear unadvisable, because in some species the size of the patches of palatine teeth 

 increase with age, thus altering their original conformation, and causing one patch to imjjinge on its 

 neighbour. 



There is likewise another question as regards the palatine teeth in these fishes, in Arius j alius there are 

 usually two small patches of palatine teeth widely separated along the median line : but in some specimens 

 such are entirely absent as stated by Hamilton Buchanan, and subsequently denied by others. The 

 specimen figured has no trace of palatine teeth. Arius tenuispdnis appears to me to be so similar to^. Layardi, 

 Giinther, escepting in having no palatine teeth, that 1 cannot help thinking they are identical, but have no 

 scries to confirm or disprove this supposition. Consequently genus Hemipimelodus,X Bleeker, has its 

 representatives in India, but such are either abnormal specimens in which the pahitine teeth were absent from 

 birth, or else have become lost due to age. These species would appear to be such as have globular teeth. 



The air-vessel is not enclosed in bone, is large, heart-shaped, and internally subdivided into five chambers, 

 which communicate together anteriorly, the front one which is the largest occupies its anterior portion, behind 

 it a median septum divides it down the centre, and lateral partitions sulsdivide the posterior chambers into four. 

 (see .4. gagora, p. 4G5.) 



The breeding of these fishes is peculiar and deserves attention, the eggs of Arius are large, averaging 

 about 0-5 to 0-6 of an inch in diameter and I found many males, also of Osteogeniosus, with from 15 to 20 of them 



* Species destitute of palatine teetfi belong to genns BemipimelodAis, Bleeker. 



t Six in scime Suntli American species according to Valenciennes. 



t Dr. Uuuihcr observes, " In species wbich have ruJimciitarj- vomerine teeth, these are sometimes entirely lost wiih age." 



