70 GEOL. AND NAT. HIST. SURVEY OF MINNESOTA. 
male antenna bears a hook of moderate size. Fifth feet of female 
short, with a short stout claw and with the inner ramus as long as the 
basal joint of the outer, one-jointed. The apical joint of the outer ra- 
mus is obsolescent, bearing small spines. The male feet are almost 
exactly as in the small form of D. sicilis, but have a process on the 
basal segment of the outer ramus of the right leg. Length 1.3 mm.. 
Lake Tulan, Fresno, Cal. 
*Diaptomus novamexicanus Sp. n. 
PLATE VI, Fies. 7-10: 
Inter minores sui generis, modice robustus. Cephalothorax latitudine maxima. 
ante medium sita. Segmentum cephalothoracis ultimum lateribus utringue mu- 
cronibus brevibus ornatum. Segmentum abdominale 1-mum utrinque mucrone brevi 
instructum. Segmentum 2-di per breve. Rami furcales segmentum antecedens 
longitudine sequantes, setis apicalibus brevibus. Antenne 1-mi paris feminz retio 
circiter ad furcam vel interdum ad finem furcz porrectz, articulis 25 composite. 
Articulus antepenultimus antennz dextre maris lamina, antice in processu ungui- 
fore, apicem articuli penultimi vix attingente, productus, armatus. Ramus exterior 
5-ti paris apud feminam 3-articulatus, processu ungtiiformi articuli secundi arcuato, 
intus ad finem denticulato; articulus ultimus distinctus, aculeis 2 brevibus ornatus. 
Ramus interior l-articulatus, articulus 1-mus rami exterioris vix longitudine fere 
equante. Pedis dextri 5-ti paris apud marem ramus interior uni-articulatus apicem 
articuli 2-di rami exterioris attingens, apice acutus, pilis obsitus. Unguis terminalis 
rami exterioris simpliciter arcuatus. Seta accessoria brevis. Pes sinister articulo 2-do. 
rami exterioris oblongovate, versus apicem intus subtilissime aculeato et duos acu- 
leos majores portante, ad basin in lamina ciliata extante. Ramus interior simplex, 
versus apicem ciliatus, vero longus et ultra medium articuli 2-di rami exterioris por- 
rectus. Animal pleurumque pellucidum, interdum czruleo vel rubro ornato. Long. 
feminze 1.1-1.2 mm. 
A small species of rather robust form found associated with D. 
albuquerquensis in the tank of the city water works of Albuquerque, 
New Mexico. The greatest width is somewhat in advance of the 
middle. The last cephalothoracic segment is ornamented with small 
spines only. The first abdominal segment bears on either side a sharp 
spine. The second segment is quite short. Stylets of moderate 
length with short sete. Antenne reach the stylets. Antepenult 
segment with alamina along its distal aspect terminating in a slightly 
curved process shorter than the penultimate segment. The segment 
following the geniculation has a hyaline lamina. The fifth foot of the 
female has a single-jointed inner ramus of considerable length armed 
at the apex with two spines and small cilia. The claw of the outer 
ramus is moderately curved and armed near the tip with a series of 
teeth, the terminal joint is distinct and bears two small spines. The 
inner rami of the male feet of the fifth pair are simple and rather 
long. The terminal claw of the right leg is slightly curved and of 
moderate length, while the accessory spine is nearer the apex of its. 
tS ye 
Par ans 
4 
