AND ENDOSKELETAL SYSTEMS OF SCORPIO. 351 
ventral to the lateral median process, and to the arthrodial membrane between the 
metasternite and the coxal joint of the sixth appendage. 
IV. Muscles attached to the Suprapectinal Chondrite. 
The lateral antero-posterior muscle (25) of the first segment of the mesosoma has 
already been mentioned as being attached posteriorly to the suprapectinal chondrite 
and anteriorly to the plastron. 
The lateral antero-posterior muscle (26) of the second segment of the mesosoma is 
attached anteriorly to the suprapectinal chondrite. 
The dorso-suprapectinal-chondrite muscle (66) of the dorso-ventral series of muscles is 
attached to the superior surface of the suprapectinal chondrite, as has been mentioned 
above in speaking of the dorso-ventral muscles. 
The plastron-suprapectinal-chondrite muscle (86) has been mentioned with the 
muscles attached to the plastron as being attached anteriorly to the plastron and poste- 
riorly to the suprapectinal chondrite. 
The epimero-suprapectinal-chondrite muscle (87) is a small muscle attached to the 
most lateral portion of the suprapectinal chondrite. It is also attached to the epimeron 
lateral to the pecten. 
The posterior pectino-suprapectinal-chondrite muscle (88) is a small but broad muscle 
which runs from the inferior portion of the suprapectinal chondrite to the posterior 
margin of the pectine. 
The sterno-suprapectinal-chondrite muscle (89) starts from the suprapectinal chon- 
drite, and runs to the sclerite between the pair of pectines. 
The anterior pectino-suprapectinal-chondrite muscle (90) is a small but broad muscle 
which runs from the inferior surface of the suprapectina] chondrite to the anterior 
margin of the pecten. 
The interior pectino-suprapectinal-chondrite muscle (91) is a small muscle attached 
to the median part of the suprapectinal chondrite, which runs down to the interior 
margin of the pecten. 
The exterior pectino-suprapectinal-chondrite muscle (92) is attached to the supra- 
pectinal chondrite, and runs down to the exterior margin of the pecten. 
V. Muscles attached to the Preoral Entosclerite. (See Plate LX XIX. 
figs. 11, 12, and 16.) 
Muscles are distributed from the preoral entosclerite to the dorsal surface, the coxal 
entosclerite of the first appendage, and to the pharynx. There are four muscles to the 
dorsal surface, of which one has a median attachment, the other three have lateral 
attachments. 
The median dorso-preoral entosclerite muscle (62) is attached to the anterior part of 
VOL. XI.—ParT x. No. 6.—WMay, 1885, 3G 
