FISHES OF SACRAMENTO-SAN JOAQUIN BASIN. 149 
DistRIBUTION OF FRESHWATER FISHES IN SACRAMENTO-SAN JOAQUIN BasIN. 
Basin divisions. 
- Found 
~ . Pounc 
Sp Ss. : “ 
pecies Pitt Lahon- | Sacra- | only in 
River. tan. mento. Cali- 
} fornia. 
= — — nn St JAS —— | = | = 
oy BarrG) PG Cha EA A ise ae aoe a il eee ea Re eee See eee > | hodeeeeee x ee soe se Se 
PALM CUE CLO ML ibe Seniesa te Seoen cle ee anette e fered se ae sce acmed micas soot eden ese eee meemiccs|pacnaeccws x< 
8. Pantosteus lahontan....-.....-...............--. So iaio Se alanine oceit awlctan aie aia ale iere eieela ees 
. Catostomus microps. . 
1 
v4 
3 
4 
5. Catostomus tahoensis 
6 
“f 
8. 
SCHEONTOUI US OCCLOOD DUS Gat co Mee ees atans. cect ercs ars Umansacss decenee ees 2 X x Xx 
MOTHNOUOM DUCTOLOMIGOUIS emcee cone tinea oe cas cbs ch cnc cccoucnacs-comcciecccctcntfarewanencaleescecaet x x 
Pea tey ORC M UIC Het aa ei scemecian nae einea sate se Ch cm rcteties sci eee ocean ae oe nea a eden ecb ance x 
Rep HAO OGHICONGCONN AIMS eae meses ee Cas cmitse sacha sanerowece aceael) Nl [eigen act x x 
POP Ounat Mus runCrOlDIOOLUNee wets amen cen ee SoC Sonos baa ecaccceaecass esl ek rawacepteebomeums x Oe 
Wo Ter At one e UTE ad ete RS oe os 5 Acne Bris ene = phe ee i ee SE PRR aise) Ulm Ga Bag) (acaba! EP | x x 
ISLC SORE CL ALMA ICSE Ciao ee eee matd ectercita aincs ooo ee aia Gat oa ne aac ou wee eatieen eae Quen oe cee eb ae Soceecwes™ x > 
LODGING Lit CONIGIINS Ss otf tas ee sole moat soos ee Seok anccnuccen conscbeieeecncess eee eee x Se 
PARP ALCISGHA CEROR IIS amie ama tea tome nate some oni on cmmabale vc cereale Soe Raat 5 x 4 [Eee cnact 
Ome SE ICOLON aware ot eattee costa t nw acetamec rose denchwneccsccacsececclncenenses x esee toc | x Waris cic ons 
UTh LRU) ena) oe Se hs SAP Gone oe ase SRO eer ee SBC eH Ses EE sae apa Tae i) i raeiereste weer x | x 
fem ORO DURUS len enna ch peita een see cee ae Salcin ac asesn ie ce slesce cs clones ac x Xx ye ow lenancagesd 
ptr ELST RTU CL OLS pee eee arenes tea te ae oe eee Set NEG, i Ca ecnina ce cisesccmsve woes e x x x [eee sees 
SAMO RTAIT ES PERU TMs onset tie Se a Wales 5 Neen cea wcireeecicerawpcemer es seus (oodecueens|+-cemeraes x |sdeeeseecs 
PERGURLSEONCELIG (COLA PUTA Chus ce sacccs cone nanie came sias ce o2scacaeere, ~acicwecuest eck t]oscecatconlescscacecct@! 3 So) bre ce dese 
DIPATAUO TUBA LONE DUNG wesc Sacre an eam ane ate ccaekln gid tap acc talnc caw eeecelesmacencee < x 
SOPEELORLOROCAN POS MESS ty ie aes mi anaes Gomes seuesesreen asec ses Peon eae ee OC oem eers Xx x 
Po MOOUULIS ED ELEINB A ere i aS ene cian oaclon Sects codise cee sees due cence eetbecesesees x eee 3 Oey ea eee m4 
20 LOTTIE We nian cee Shi Sa gsine 0 566 ec ASS Ce pace OCR DOSE PED OOS Season > bensoe aac ese = ccc: Hee |oae aes 
aren OUUU: MOSES arene ett ee eam ocean See wane ans sete ea enae esa secesascecne x | x > SN Po mree Sao 
Bed red RAEI TRAD Nese ore eee Pee alee neta setae can aawakic oF anoint acest temas eke Bei WranS nA Ee goanosent x 
eC TS GLO Ge een me a terse hacen aera to cararn eee Scinidu am os a soe erie Seats cree Petr aecentc | pi aaee [ieee tered Pee ee Ae 
TE Se searee ice ontnoe dance Bac See EES ea Gene EEE Mee eee ener 13 8 21 14 
SUMMARY OF VARIATIONS. 
The following species deserve special notice on account of their remarkable 
variations: 
Catostomus occidentalis varies in scales of lateral line from 60 to 84, and in rays 
of dorsal from 11 to 14. The size of the lips varies enormously, being almost twice 
as great in some localities as in others. 
Lavinia exilicauda. The only important variation in this species is in the 
presence or absence of the horny sheath of the lower jaw. 
Ptychocheilus grandis. The scales of the lateral line vary from 65 to 78, or, if 
Ptychocheilus harfordi be included, from 65 to 88. 
Rutilus bicolor has the number of scales of the lateral line ranging from 44 to 61; 
but its greatest variation is in the shape of the head, which varies from triangular 
(side view) to quadrangular. 
Rutilus symmetricus is the most variable species of the basin. The number of 
scales varies from 47 to 56; the lower jaw may or may not have a horny sheath, which 
is developed irrespective of age,sex, season, or locality; the shape of the head, depth 
of caudal peduncle, size of eye, length of fins, and general appearance all vary 
