38 Mr. ©. T. Regan— Classification of 
proximally, not or barely reaching frontals ; posterior part 
of parasphenoid more or less distinctly raised, bearing a pair 
of transverse oval facets for articulation of upper pharyngeals. 
Vertebraa 26-33 (14-11 + 12- -16); third with a pair of in- 
ferior apophyses which unite below; preecaudals with para- 
pophyses from the fourth, the last or last two pairs each 
connected by a bridge ribs, except the first, on parapo- 
physes. 
Africa and Syria. 
As restricted by the above definition this is a large and 
varied genus, which nearly corresponds to Boulenger’ 8 
section I. (scales cycloid or feebly denticulate) with the 
exception of 7’. auromarginata *, A complete revision will 
be necessary before a final decision can be reached as to 
whether it should be split up. At present I am inclined 
to recognize four subgenera, as follows:— 
I. Lower pharyngeal with short anterior blade. 
Kthmoid united with vomer by suture ............ .. Coptodon. 
Ethmoid free from vomer; maxillary concealed; inner 
edges of rami of lower jaw curved anteriorly ; 
pharyngeal teeth, slender 5 éisiijiisietndivikb’ss (a So BS Tilapia. 
Ethmoid free from vomer; outer teeth of jaws much 
expanded ; end of maxillary exposed ; inner edges 
of rami of lower jaw straight ; middle pharyngeal : 
teeth rather stout ....... eciciet cies tune erates .... Heterotilapia 
{I. Lower pharyngeal with long anterior blade ; 
maxillary concealed ; inner edges of mandibular 
rami curved anteriorly ; pharyngeal teeth small, 
slender, HUMUPOUS 4.0.3 sar ot) ds oa peseecsceses NSarotherodon. 
Of these subgenera Coptodon includes T. zillit and T. busu- 
mana, [Heterotilapia is a new subgenus formed for T. bueté?- 
kofert, which has a very characteristic dentition; the stout 
pharyngeal teeth are bicuspid, with the posterior cusp large 
and obtuse and the anterior represented by a transverse ridge 
which may bear 2 or 3 denticles. Sarotherodon (Melano- 
genes, Oreochromis) includes the species of the shirana, 
nilotica, galilea, and macrocephala groups. A species of this 
subgenus (7. nilotica) has reached Tanganyika, probably 
through Lake Kivu. 
3. NEOTILAPIA, gen. nov. 
(type Chromis tanganice, Giinth.). 
Dorsal XVI-XVII 11-13. Anal IIT 9-10. Scales 
* Otopharynz, gen. nov. (type 7’. auromarginata, Bouleng.); differs 
from Tilapia in that the prootic forms part of the pharyngeal facet on 
each side: very near Chilotilapia. 
