DEVELOPMENT OF THE SKULL IN THE BATKACHIA. 
669 
PLATE 61. 
Pipa monstrosa. — Ernbyro and ripe young. 
Fig. 1. Orbital region of chondrocranium (embryo) ; upper view, x 20 diameters. 
Fig. 2. Cranium of larger young Pipa; upper view. X 14 diameters. 
Fig. 3. The same skull ; lower view, xl4 diameters. 
Fig. 4. Part of fig. 2 ; nasal region. X 42 diameters. 
Fig. 5. The same, with investing bones removed. X 42 diameters. 
Fig. 6. Part of fig. 2 (auditory region). X 42 diameters. 
Fig. 7. Part of fig. 3 (ethmo-palatine region), x 42 diameters. 
PLATE 62. 
Pipa monstrosa. — Adult. 
Fig. 1. Cranium; upper view. X 2 diameters. 
Fig. 2. The same ; lower view. X 2 diameters. 
Fig. 3. The same ; end view. X 2 diameters. 
Fig. 4. The same ; side view. X 2 diameters. 
Fig. 5. Mandible; upper view. x2 diameters. 
Fig. 6. The same; side view. X2 diameters. 
Fig. 7. Fore part of skull, with investing bones in outline ; lower view. X 2 diameters. 
Fig. 8. Cranial elements of the same part ; lower view. X 4 diameters. 
Fig. 9. Temporal region of skull (part of fig. 4). X 6 diameters. 
The abbreviations are the same in the present paper as in the last, with a few excep- 
tions and a few additions. The terms “ suprahyomandibular ” ( s.lim .) and “ infrahyo- 
mandibular” ( i.hm .) are dropped, as they were given under a misconception as to the 
nature of the parts. The first ( s.hm .) has now to be lettered as the “ annulus tympa- 
nicus ” ( a.t .), and the second [i.hm.) is known to be the pedicle of the mandibular pier 
{pd.). The special term “columella” (co.) is here added — also “preorbital (p.ob.), 
“prenarial ligament” or “lamina” ( p.n.l .), “recurrent cartilage” or “lamina” (rc.c.), 
“ otic process ” ( ot.p .), “ thyroid gland ” ( tr.g .), “ thymus gland ” ( tm.g .) ; the “ qua- 
drate bone ” (q.) is here the “ quadrato-jugal ” (q-j.) ; the external valvular process of the 
nostril ( v.e.n .) is here the “ first upper labial ” ( u.l .). 
In this paper the distal part of the “ columella ” is the “ symplectic,” and that term 
is erroneously applied to a part of the mandible in the former paper. 
The nerves are also numbered somewhat differently, according to the new notation ; 
the “ portio mollis ” is now the 8th, the “ glossopharyngeal ” the 9th, and the “ vagus ” 
the 10th. 
