296 Mr. G. A. Boulenger on Fishes 
Silurida . 
20. Pimelodus maculatus, Lacé p. 
21. Pimelodus ornatus, K ner. 
22. Pimelodus Muellerit, Gthr. P. 
23. Pimelodus altipinnis, Stdr. M. 
24. Platystoma Vaillanti,C.& V. M. 
25. Piratinga Rousseauxti, Cast. P. 
26. Arius Herzbergit, Bl. M., P., S. 
27. Arius proops,O.& V. M. 
28. Arius luniscutis,C. & V. M. 
29. Arius rugispinis,C.& V. M., P., 8. 
30. Artus nuchalis, Gthr. M. 
31. Arius pleurops, sp.n. M. 
Palatine teeth villiform, in two widely separated transverse 
patches which are narrower than the premaxillary band. 
Depth of body 42 times in total length, length of head 332. 
Width of head 3 its length; upper surface granular poste- 
riorly ; fontanelle extending from the internarial region to 
the base of the occipital process, which is keeled, nearly as 
long as broad, and in contact with a very small crescentic 
bone at the base of the dorsal; naked parts of head with 
reticulating or arborescent canals ; eye perfectly lateral, just 
behind and on a level with the angle of the mouth, its 
diameter 5 times in length of head, 14 in length of snout, 24 
in interorbital width ; barbels short, not reaching gill-cleft. 
Dorsal I 6; spine nearly 3 length of head, granular in front, 
with antrorse serration behind. Adipose fin small, its base 4 
that of dorsal. Pectoral spine slightly shorter than dorsal, 
likewise granular in front and serrated behind. Anal 20, its 
longest rays 2 length of head. Caudal deeply forked. 
Brown above, silvery beneath. 
Total length 170 millim. 
The single specimen sheltered in its mouth eighteen eggs, 
8 millim. in diameter, with embryos in an advanced state of 
development. 
32. Ailurichthys Gronovit,C.& V. M. 
33. Auchentpterus striatulus, Stdr. 
34, Auchenipterus nodosus, Bl. M. 
Differs from the typical form in having the dorsal and 
