ors al ▁surface . ▁The ▁e y est al ks ▁are ▁short , ▁but ▁bear ▁large ▁black ▁comp ound ▁eyes . ▁P . ▁arm atus ▁can ▁be ▁told ▁apart ▁from ▁the ▁similar ▁P . ▁och ot ensis ▁by ▁the ▁sp ines ▁on ▁its ▁cla ws , ▁which ▁in ▁P . ▁och ot ensis ▁are ▁replaced ▁by ▁gran ules . ▁The ▁two ▁species ▁are ▁so ▁similar ▁that ▁they ▁have ▁sometimes ▁been ▁considered ▁members ▁of ▁the ▁same ▁species , ▁but ▁are ▁now ▁generally ▁thought ▁to ▁be ▁two ▁distinct ▁species . ▁ ▁E col ogy ▁P . ▁arm atus ▁lives ▁on ▁a ▁variety ▁of ▁substr ates , ▁being ▁particularly ▁abund ant ▁in ▁sea ▁pen ▁b eds , ▁at ▁depth s ▁of ▁up ▁to ▁ ▁Type ▁spec imen ▁P . ▁arm atus ▁was ▁originally ▁described ▁( under ▁the ▁name ▁Bern hard us ▁arm atus ) ▁from ▁Pu get ▁Sound ▁by ▁James ▁D w ight ▁D ana . ▁The ▁ ▁hol ot ype ▁of ▁P . ▁arm atus ▁was ▁lost ▁in ▁the ▁Great ▁Chicago ▁Fire ▁of ▁ 1 8 7 1 , ▁and ▁has ▁been ▁replaced ▁with ▁a ▁lect ot ype . ▁ ▁References ▁ ▁Category : H erm it ▁c rab s ▁Category : Cr ust ace ans ▁of ▁the ▁eastern ▁Pacific ▁Ocean ▁Category : Cr ust ace ans ▁described ▁in ▁ 1 8 5 1 <0x0A> </s> ▁The ▁Ber etta ▁Model ▁ 1 9 3 4 ▁is ▁a ▁compact , ▁semi - autom atic ▁p istol ▁which ▁was ▁issued ▁as ▁a ▁standard ▁service ▁fire arm ▁to