190 
While this series has proven sufficient to establish the fact that 
Batrachoseps is entirely devoid of larynx or trachea, I can state nothing 
concerning the origins of the muscles forming the band across the 
pharynx. This band shows, however, no separation into digastricus 
pharyngis and dorso-laryngeus as in Plethodon, it is ex- 
tremely thick and powerful, and only the anterior half is divided by 
a median ventral raphé. For the rest of their course the fibres pass 
uninterruptedly from one side to the other. 
Manculus. 
For this genus I have a cross series of Manculus quadridigitatus, 
including the entire cervical region from otic capsules to sternum. 
From this the following facts can be determined: 
The laryngeal muscles form a single broad band crossed by 
three raphés, one median and two lateral. Of this band, a very few 
fibres, representing the dorso-laryngeus, arise from the dorsal 
integument and form a very delicate band, as in Spelerpes, which 
fuses with the main mass. The rest of the muscle arises from the 
side of the skull (otic region). The more posterior fibres do not meet 
in the mid ventral line, but are interrupted by the anterior portion 
of the pericardium, to the outer surface of which they insert. This 
general condition is much the same as in Spelerpes and is satisfac- 
torily explained by 
MANCULUS @UADRIDIAaITATUS. a fusion and loss of 
identity of the two 
elements distinct in 
Plethodon. The few 
fibres of origin from 
the dorsal integu- 
ment, and the inser- 
tion of the posterior 
Fig. 7. Cross-section 
through otie region of 
Manculus. Ph, Pharynx. 
Ph, ac. Accessory pharyn- 
geal cavity. Ps.t. Para- 
sphenoid tooth. hy Cornu 
of hyoid. 
fibres into the pericardium are the elements belonging to dorso- 
laryngeus; the cranial origin of the most of the fibres, the lateral 
raphés and the insertion of the mid-line are characters distinctive 
of digastricus pharyngeus. Below them are a few oeso- 
phageal fibres, but not as marked as in Spelerpes. The most marked 
