292 SILUEIDJE. 



In addition to these specimens, I have examined the types of Clarias lazera and 

 C. syriacus preserved in the Paris Mnsenm. 



The former (Nile : Lefebvre) measures 300 millimetres ; the vomerine teeth are all 

 granular and form a band which is considerably broader than the prsemaxillary band ; 

 about 75 gill-rakers on the anterior arch. The latter (Syria: Bove), a skin in spirit, 

 500 millimetres long, is specifically identical ; there is no postero-median process to 

 the band of granular vomerine teeth, which, in the middle, is once and two-thirds as 

 broad as the prsemaxillary band. 



Mr. Loat observes : — " Fairly numerous in Lakes Menzaleh and Borollos, but mostly 

 during the Nile time. In Lake Edku it is caught during the Nile time, but not at 

 other times. Found all the year round in Lake Mareotis. At Eosetta all the year 

 round, mostly during the Nile time. It is chiefly found in localities with shallow 

 water with reeds and mud, in irrigation trenches, and ponds left by receding Nile." 



Some specimens found near Damietta bore, partly imbedded in the vent, parasitic 

 Copepods of the genus Lernwocera, indistinguishable, Dr. Caiman tells me, from those 

 noticed in Polyptems (supra, p. 8). The hinder part of the body of the parasite, 

 projecting from the vent of the fish, was covered with Vorticellse, giving it a fluffy 

 appearance. 



5. CLARIAS TSANENSIS. 



(Plate LI. fig. 2.) 



Boulenger, Ann. & Mag. N. H. (7) x. 1902, p. 438. 



Depth of body six and a half to seven and a half times in the total length, length of 

 head three and one-eighth to three and four-fifths times. Head once and a half to 

 once and two-thirds as long as broad, perfectly smooth above; vertex very strongly 

 flattened, almost concave in the adult; occipital process angular; frontal fontanelle 

 knife-shaped, three to four times as long as broad, four to five times in the length of 

 the head ; occipital fontanelle indistinct ; eye twice and a half (young) to four times 

 in the length of the snout, four to six and two-thirds times in the interorbital width ; 

 width of mouth nearly equal to the interorbital width ; band of praemaxillary teeth four 

 to five and a half times as long as broad ; vomerine teeth granular, forming a crescentic 

 band which is as broad as the prsemaxillary band. Nasal barbel one-third to one-half 

 the length of the head (three-fourths in the very young) ; maxillary barbel three- 

 fourths to once the length of the head (longer in the very young), reaching the base 

 or the extremity of the pectoral spine ; outer mandibular barbels one-half to four-fifths 

 the length of the head (as long as the head in the very young). Gill-rakers long 

 and closely-set, 45 (young) to 70 on anterior arch. Dorsal fin with 78 to 85 rays, its 



