Vou.2]  Esterly—Copepoda of the San Diego Region. 121 
47. Fifth feet, especially the left, with several apical appendages. .. 
g Oth Canoe AROS AE OLE Chad Oop OueRD PRCANG ICID OOS ner oe RCo eNO Stephusg 
47, Fifth feet slender, stylet-like, with a few short needles or with 
but one needle or hook-like appendage. .¢.%..........o20.0-- 48 
48. Fifth feet slender, stylet-shaped, about as long as the abdomen... 
5, 5 S-otto craic yO RL DIG Die eraraer Nui mis ean o Craukonn iene Pseudocalanus4 
48. These shorter than the abdomen, the right foot with a terminal 
INGYOLE 5 refage Rec REG eR aeons Mee Oy Geel “Wins ae Seat rp a ee Drepanopust 
fo cephalothorax, broad to globular 222.100 aasoosse ase ens esos Phaenna 
49. Cephalothorax elongate, ellipsoidal (figs. 26a, 29).............. 50 
DO a Ehead distin chy trom, borax, Was coe Lie ete ave kee ele Xanthocalanus 
50 tead fuged with thorax’ (figs. 26a,°27)). .< iene 2 ne conan 56 *Scolecithrix 
SPP t esr OOts LACKING. Vier. as, se eoaetne A size en aenv ee Mme See eee io apsticc de, as 52 
ep L Hae OOt MORESOMEN: S7..ctr.< hiatal etorsiers a Sait st tale carte miele teres senate oes 59 
52. Last thoracic segment prolonged laterally into a long, pointed 
PROCESS ACH Shea, SU tarsi sleet cecle ete teriatcl kisah aL ev 53 
52, Lateral angles of last thoracic segment rounded or slightly pointed 
(CaicseeallG cea) eon aetna eracsce ee aed eters Suet mt LS aio 56 
53. Bristles of the sixth joint from the last in the anterior antennae 
Ehnickwan(distrans merselyzerinoe dimen eies esd crernie seers Bradyidius? 
Se}, MUNESS lous, Gh Ta@ Wel WOM. Soo ole oaaoacadenugopcudGusan6 54 
o4. Rostrum with two heavy teeth (fig. l4a)............... * Aetideus? 
54. Rostrum with one point (fig. 150) or lacking.................. 55 
Sas Owiise weweMMIS| Che Tudshy TOON Bsomamiecl FogoonancoucaboouccgDc Chiridius? 
DI Oucer TaMUs oO fins oot 2-joimbeds iow W5q)e ea. seh ee *Gaidius? 
56. Rami of posterior antennae about equal in length........ *EuchaetaQ 
56. Outer ramus at least 1144 times as long as the inner ramus 
(GIN OCI aesdevencusyer fay ope ener eters ee te ene Sterere tenes Stayt heiar apes, auelarancatleir 57 
57. Inner border of first basal of fourth foot naked or feathered..... 58 
57. Inner border with teeth or spines (figs. 19b, 20d)....... *Euchirella? 
58. Head with or without crest (figs. 16a, 17a); last thoracic segment 
not produced into spines or blunt processes........ *Undeuchaeta? 
58. Head with median crest, last thoracic segment produced into 
bluntyprocessess (mot spimes))i tans... sas ss esse Chirundina? 
59. Last thoracic segment on each side with a strong point (fig. 
NAC asap tN Pape Maton ee rica ceusctiel sy asc ek dite) ah dito er lepps telcos saver ont clove * Aetidiuss 
59 hast ibonacresseament noun ded silos 20 Gees ree ciel is 60 
60. Right fifth foot with forceps (figs. 20b, 21b)............ Euchirellag 
60. Right fifth foot ends in a stylet without forceps (fig. 23a).... 61 
61. Inner rami of posterior antennae at most equal in length to the 
OMFS Leeds SenchO Gi GLES.O1 SO OICATE PSEOW Onl REET IRON ONO ed Euchaetag 
. Inner rami of posterior antennae over half the length of 
Ce MOUECI, acy seve. sSareh syokor Siemens oe aoe tateda ce w ahsnele is aie tousle *Undeuchaetat 
