1921 J Schmilt: The Marine Decapod Crustacea of California 17 



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Fig. 7. Ventral view of anterior part of body of a brachyuran decapod, 

 roof of the buccal cavity is known as the endostome or palate. 



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Measurements. — Length is always measured on the median line 

 from the anterior to the posterior margin. The length of the rostrum 

 is measured from the line connecting, in shrimps, the posterior, and 

 in crabs the upper margins of the orbits. "The length of segments 

 is measured on the upper or anterior margin. The length of the 

 whole cheliped or leg is measured on the lower margin from the 

 articulation of the coxa with the sternum to the tip of the dactylus. 

 The length of the immovable finger is measured from the tip to the 

 extremity of the sinus between the fingers." (Rathbun, 1918, p. 8.) 



"Width of carapace, and of segments of the chelipeds and legs is 

 measured at the widest part. "The fronto-orbital width is measured 

 from the outer angle of one orbit to the outer angle of the other." 

 In crabs ' ' the width of the rostrum is measured at its posterior end. ' ' 

 {Op. tit., p. 8.) 



