424 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 
The lining of the buccal and branchial cavities is blackish, except 
along the margin of the mouth; the peritoneum is blackish brown, 
underlaid with silvery. : 
Table of measurements in hundredths of length to anus. 
PMP APPEASE AO ONS ei BORO CORO O CaO SO OS DOD ASS doo Se HASeSsa0ec nogbsaceas see |  §202 5648 | 5467 
Totallenethvinmml =e. a-sceetee ete cee | 280+ 1278) i GOS 
Length to anus in mm.............---- 82 82057] 71 
Ibeneth: of headeeseccs ce eee eeaser 73 72 74 
ene thiOnOrpigeeesss-- = seen aan 18 18 18 
Width ofinterorbital.......-.-.---- 17 18 16.5 
Width of suborbital. - - - | 11 11 ll 
Orbit to preopercles-/-- =... ---..--- | 29 30 29 
Length of snout......-...--.----- | 24 23 25 
Wadthioisnouteecess secant 29 27 28 
Length of upper jaw....--------- 22 20 21 
ensth of Darbelicece =-n-cece neces es Ste if ire | 6 
MepEhvor Ody sosmsieciee =a eater falas eleteletelale tleieiatelal ere siete etetele ete aloe aet | 46 46 | 47 
With of Dodiya = saccen eee eee sensor teen eee eee ete Renee ae eee ae | 31 34. 29 
SAT AES Rive Si ae SEB OUCR ME SOU ab Sr aD oe Oa o soon auagnenar SanSSSs0e ciab ae] 13 13.5 15 
Anus towventrall. soses cocmee scat tee aa eee ee eae Lisdetisaee cose 18 2159) 20 
Ventral toistbrnis es Semone so erie ee Eee coe eee ao aeeenaee ee | 22 O38 ul 23 
Heizht tole secondtd orsaluspine sere -cecns enemneeeisise see seee oaneme eae eise rt | 139 146.5 163 
LE LSTA U AOI HL SUN 6 eo Ko) EN oy eR am ecieoes JODO noodc bs Sodane sucdunonescasgCcdGes 56.5 HY AS hel Pee se 
bene phot wrst. dG OFS DESO anc oa ase mele me eteile me elelatm ln ala lsiateietelslainiaretete rater 18 Ligess| 17 
enP th) Of AMLErGOrsAlus pace socieeemem ees aciaeeek ee eis ieee ea eaten 13.5 16 14 
Length ob pectoral atacae. cane «seco sete emt salah Sate aera seein ee 38 2235) lee aces 
Length of outer ventral ray...-..--- BASIS ROR Soa Qa SAGA ABe och aba aCOOECOLE 43 40 | 31 
engethiof seconds yentralira yer <a se= e a eeeetelce mie eee mee eater 26 PY fame 22 
1A pseudocaudal developed. 
(Ayostomus, meaning hog-mouth.) 
Genus COELORHYNCHUS Giorna. 
The fauna of the Philippine Islands and the adjacent region to 
the southward has proved to be exceptionally rich in the species of 
Coelorhynchus. The region appears to be the center of their dis- 
tribution, for in no other similar area in any of the seas is there 
known anything like the variety of species which occurs there. Of 
special note are the humerous species of the C. notatus and the 
C. japonicus groups. The subgenus Quincunciasis unknown else- 
where. In this region there are now known 23 species, or 45 per 
cent, of the total number in the world.t Despite the occurrence of 
this large number of species, none of them, with the exception of 
QO. parallelus, has been discovered in other faunal regions, although 
some of them have close representatives in the Indian, Japanese, and 
Hawaiian faunas. These facts of distribution have already been 
discussed in the introduction. 
The following analytical key has been arranged, as far as possible, 
to indicate the mutual relationships of the subgenera and species, 
each one being most closely related to the group or species preceding 
and following it. 
1 The authors have examined 42 of the 51 known species. 
—_ ee 
