1877.] 91 
[Cope. 
possesses the same produced, flattened muzzle, with distinct eye, and the 
coloration is similar, but the position of the tentacular fossa is quite differ- 
ent, and the general form is more elongate and slender. The diameter is 
about the same. Length, .425; diameter, .017. 
Coast of Eastern Costa Rica ; W. M. Gabb. 
SrpHONOPS simMuSs Cope. 
Tentacular fossa close to eye ; annuli complete ; muzzle wide, truncate, 
nostrils terminal ; annuli 228 ; anterior 8 undivided ; 22 posterior fully di- 
vided by intermediate plice. 
The form of the head of this species is different from that of any other 
Siphonops of Mexico or Central America, and its annuli are more numer- 
ous. They continue to the anus, and those of the principal series are no- 
where divided on the middle line. The form is not slender, but is more so 
than in the S. mexicanus, resembling in this respect the S. proximus. 
Length, .308 ; diameter at middle, .011. Color dark brown ; below a little 
paler. 
This species was found in Costa Rica, the exact locality being uncertain. 
From Dr. von Franzius. 
SIPHONOPS OLIGOZONUS Cope. 
Tentacular fossa close to eye ; many annuli incomplete ; muzzle narrow, 
projecting ; eye invisible ; nostrils lateral ; annuli of principal series 119, 
of which 14 anterior and 42 posterior are complete ; of second series (none 
in anterior 72 annuli), 34 incomplete and 13 complete. 
This Batrachian resembles at first sight the Caecilia ochrocephala, as it 
possesses the same yellowish head and brown plumbeous body. It is 
abundantly distinct from the other species of the genus in various respects, 
combining the interrupted annuli of some of the Brazilian species, with a 
narrower, projecting muzzle, and invisible eye. The annuli continue to 
the vent, and those of the secondary series commence much posterior to 
ao 
the point of beginning in the other species. Length, 0.263 ; diameter, .005. 
The precise habitat of this species is uncertain. 
CAECILIA ISTHMICA Cope. 
teneral form robust. Muzzle flat, rather wide, and projecting far be- 
yond the mouth. Tentacular fossa near the edge of the lip a little behind 
and below the line of the nostril. Eye distinct. Annuli one hundred and 
forty-two, of which only the last sixteen surround the body, the anterior 
one hundred and twenty-six being interrupted both on the dorsal and ab- 
dominal lines. Between the last seven rings are additional plice, which 
cross the dorsal line and extend on the side, but are not continued across 
the abdominal line. Length, .570 mm.; diameter (which is about uniform), 
.020; length to rictus oris, .017. The general color in alcohol is dark 
brown ; the inferior surface is a little paler. 
This species was included in the collection made by Commander Selfridge 
