8 



BULLETIN 97, UNITED STATES NATIONAL MUSEUM. 



SuMepntic region, that area below the hepatic region and below the lateral 



border of the carapace. 

 Suborbital region, the narrow space bordering the lower margin of the orbit; 



not always distinguishable. 

 Telson, the terminal segment of the abdomen. See Abdomen. 

 Thumb, the immovable finger of the cheliped. 

 Vrogastric lobe, the postero-median lobe of the gastric region. Sometimes called 



the genital region. 

 Wrist, the carpus of a cheliped. 



Explanation of measurements. 



The length of the carapace, unless otherwise stated, is measured 

 on the median line, from the anterior to the posterior margin. 



The width of the carapace is measured at the widest part. 



The fronto-orbital width or exorbital width is measured from the 

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



The length of the rostrum is measured from the tip to the posterior 

 line of the upper margins of the orbits. 



The width of the rostrum is measured at its posterior end. 



The length of the segments of the chelipeds and legs 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 width of the segments of the chelipeds and legs is measured 

 at the widest part. 



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

 the extremity of the sinus between the fingers. 



Character of bottom. 



Under " Material examined," the abbreviations indicating the 

 character of the bottom, are those employed by the Bureau of Fish- 

 eries. Nouns begin with a capital, adjectives with a small letter. 



bk black 



br brown 



brk broken 



bu blue 



Co coral 



crs coarse 



dk dark 



fne fine 



For foramlnifera 



G gravel 



Glob globigerina 



gn green 



gy gray 



hrd hard 



Ige large 



It light 



M mud 



Oz ooze 



P pebbles 



Ptr Pteropod 



R rock 



rd red 



Kf reef 



rky rocky 



S sand 



sctrd scattered 



sft .soft 



Sh shells 



sm small 



Sp specks 



St stones 



stky sticky 



vol volcanic 



W seaweed 



wh white 



yl yellow 



Additional abbreviations and notes. 

 In the synonymy an attempt has been made to give all the different 

 names or combinations which have been used, but not all the refer- 

 ences to a species. 



