1893.] On the Genera of the Dipnoi Dipneumones. 931 
cartilaginous. The pectorals and pelvic appendages lack a 
membranous edging. The pectorals are slender and com- 
pressed, while the pelvic appendages are stouter and conical 
in shape. 
The scales are disposed in longitudinal rows, 10 in each, and 
are of a dark brownish purple color, with distinct blotches 
except on the belly. The lateral line is double. The eyes are 
small and lie beneath the skin. The branchial openings are 
very narrow, and are protected by thick fleshy flaps. Exter- 
nal gills are absent, and the internal gills cannot be seen 
through the deep and narrow branchial slit. The mouth has 
fleshy lips. The gill-clefts are four in number, tke fourth being 
much reduced. The three free branchial arches are fringed 
with conical papillae. The cloacal opening lies 10 mm. to the 
left of the median ventral line. 
The sixth specimen comes from the same hands, and is in 
the Florence Natural History Museum. 
It is much to be desired that these well-preserved specimens 
may become the means of clearing up many points in our 
account of the anatomy of the Dipneumonous Dipnoi. 
? Jenaische Zeitschrift Bd. XI, 1885. 
3 Schneider, A., Uber die Flosen der Dipnoi und die Systematik von Lepidesiven und 
Protopterus, Pier Anzeiger, No. 231, 1886. 
* Baur, G., Lepidosiren paradoxa. Zoologischer Jahrbücher, IT, 1887. 
? The following notes on the statements given by different authors may be of interest 
in this connection 
Wiedersheim (Lehrbuch, p. 608) says Protopterus has 6 gill-bars and 5 gill-slits, with 
ree and one-half gills 
Owen (Comp. Anat.. p. 468-481, ’82, '85, '86) gives the same number of gill-bars, 
but says that there are 2 biserial, and 1 uniserial gill, besides which there is the 
opercular gill attached to the membrane supported by the hyoid. That ** three seem- 
ingly analogous filaments (i. e., analogous to the embryonic external gills of Elasmo- 
branchs) are retained on each si e lo a longer period in o Lra annectens, but 
lose their vascular and T character before they are absorbed.” 
Parker gives (Trans. Roy. Irish. Acad., V. 30, pt.3, p. 161) 5 gill-bars and 4 gill- 
clefts, exclusive of the spiracle or hyobranchial. 
There is a T of one "oe between Parker and all other observers. There 
. isa further d cy among observers as to the number of gills. 
ores paradoso, Bichon and Hyrtl disagree ; as to the number of T aehan, 
sii: fas. h 
but Hyrtl, who worked over th P i o that th P absent on 
