1895.] FEOM MATTO 6EOSSO AND PARAGUAY. 525 



Brown above, whitish beneath ; fins uniform or ^^nth small blackish 

 spots. 



Total length 80 miUim. 



Several specimens from Descalvados, Matto G-rosso. 



This species is named after Prof. C. Eigeumaun, the author of 

 the excellent Synopsis of South American Silui-oid Fishes. It 

 conhects the sections Oxydoras and Mhinodoras as defined bj' that 

 author, agreeing with the former in the serrature of the dorsal 

 spine, with the latter in all other respects. 



5. Callichthys pectoralis, sp. n. 



Depth of body 31 to 3g times in total length. Head depressed, 

 broader than deep, 34 times in total length, without bristles on 

 the sides ; diameter of eye 6 times in length of head, 4 times in 

 interorbital width : suborbital bone narrow ; occipital bone pointed 

 in front, not reaching i'rontal fontauelie : inner barbels half total 

 length. Pectoral spine | length of head, covered with fine 

 bristles, serrated on the inner side. Dorsal I 7 ; spine nearly k 

 length of head. Anal 15. A pair of large pectoral plates, in 

 contact anteriorly, or narrowly separated, their inner borders 

 diverging behind. Shields on body reaching to base of dorsal fins, 

 23 above and 22 below lateral line ; 3 or 4 pairs and 5 to 7 

 azygos shields between the two dorsal fins. Caudal rounded. 

 Dark brown, with small blackish spots. 



Total length 85 millim. 



Several specimens from Monte Sociedad, Paraguayan Cbaco. 



This species is nearest alhed to C thoracatus, C. & V., and 

 C. longifilis, C. & V., but differs in the larger pectoral plates, the 

 wide separation between the frontal fontanelle and the occipital 

 bone, and in the smaller number of anal rays. 



6. Plecostomtjs ternetzi, sp. n. 



Head as long as broad, 3 times in total length ; three very 

 obtuse keels ; snout i-ounded, entirely granulated ; diameter of 

 eye 7 times in length of head, 4 times in length of snout, 2^ times 

 in interorbital width ; barbel as long as diameter of eye ; 44 teetli 

 on each side in the upper jaw, and about as many in the lower 

 jaw ; interopercle with very small spines. Sides of thi-oat, thorax, 

 and middle of belly covered with small shields. Dorsal I 7 ; first 

 ray as long as head, reaching adipose fin. Pectoral spine as long 

 as head, strong, with small curved spines. Ventrals I 5, first ray 

 a little shorter than head. Anal I 4. Lower caudal rays very 

 long, as long as head, t\vice as long as upper. Depth of caudal 

 peduncle 2^ in distance between anal and caudal fins. Post- 

 humeral keel very obtuse and short, not extending beyond base of 

 ventral. Scutes on body rough and spinulose but not keeled; 

 lat. 1. 25 ; 14 scutes between the anal and caudal fins. Uniform 

 oUve above, white beneath. 



Total length 240 millim. 



