352 MISS E. J. BECK ON THE MUSCULAR 
the preoral entosclerite, and runs straight up, being attached to the carapace near the 
median line (one on each side). It has been mentioned before amongst the dorso- 
ventral muscles. 
The anterior latero-dorsal preoral entosclerite muscle (93) is attached to the anterior 
part of the preoral entosclerite. It runs underneath the coxal entosclerite of the first 
appendage, and is attached to the lateral part of the carapace. 
The median latero-dorsal preoral entosclerite muscle (94) is attached to the posterior 
process of the preoral entosclerite, and runs laterally to the carapace, to which it is 
attached. 
The posterior latero-dorsal preoral entosclerite muscle (95) is attached to the posterior 
part of the posterior process of the preoral entosclerite, and runs laterally to the cara- 
pace, to which it is attached. 
The anterior first-coxal-entosclerite preoral-entosclerite muscle (96) is a broad muscle 
attached to the interior surface of the posterior process of the preoral entosclerite and 
to the interior surface of the first coxal entosclerite. 
The posterior jirst-coxal-entosclerite preoral-entosclerite muscle (97) is a small muscle 
attached to the posterior end of the posterior process of the preoral entosclerite and to 
the posterior portion of the first coxal entosclerite. 
The anterior preoral entosclerite pharyngeal muscle (98) (Pl. LX XTX. fig. 12) is a 
small muscle attached to the interior surface of the anterior portion of the preoral 
entosclerite, and runs down to the pharynx, to which it is attached on its superior 
surface. 
The posterior preoral entosclerite pharyngeal muscle (99) (Pl. LXXITX. fig. 11) is a 
larger muscle, attached to the interior surface of the preoral entosclerite. It runs 
horizontally towards the similar muscle of the other side, and is attached to the lateral 
walls of the pharynx. 
VI. Muscles to the Appendages. 
Prosoma.—The muscles belonging to the appendages of the prosoma are of two 
kinds, intrinsic and extrinsic. 
Intrinsic Muscles.—Of the intrinsic muscles, I shall only speak of those which run 
inwards from the appendages, and are attached internally to the coxal entosclerite or 
to the interior margin of the coxal sclerite. In speaking of the interior margin of the 
coxal and deutomerite sclerites I refer to that margin nearest to the body of the 
animal. 
The eaterior jirst-coval entosclerite-deutomerite muscle (100) is a broad muscle attached 
posteriorly to the exterior margin of the coxal entosclerite and anteriorly to the interior 
margin ot the deutomerite sclerite of the first appendage. 
The interior jirst-coxal entosclerite-deutomerite muscle (101) is a narrow muscle 
