10 ACARIDEA. 
glandula dorsualis lutea, antice lata, quadrifurcata, postice ramulos duos angustos laterales emittens. Pedum 
par primum ceteris haud crassius, par ultimum ceteris longius. Lamine genitales parve, se invicem 
angulis internis tangentes, obtuse pentagone ; stigmatibus majoribus quinis, minoribus binis instruct. 
Long. 0°5 millim. 
Hab. GuaTEMALA, near the city (Stoll). 
Body ovoid, convex, transparent; brownish-white, like the legs and palpi; the dorsal 
patch large, blackish-brown, separated into seven single spots by the orange-coloured 
dorsal gland ; the latter divided in its anterior half into two bifurcate branches, whilst 
at its posterior end it emits two small and narrow lateral branches. The first and 
second pairs of legs bear on their lower surface a few pairs of long, squarrose spines, 
which are indistinctly serrate at the end and inserted behind tooth-like elevations of the 
epidermis; the third pair with a pinnate bristle at the apical end of the fifth joint, and 
also with several swimming-hairs beneath; the fourth pair with a few short spines 
beneath, the spines gradually becoming longer towards the apex of the joints, and the 
apical end of the third, fourth, and fifth joints with a short, pinnate bristle, and towards 
the apices of the same joints some tufts of long swimming-hairs. ‘The genital plates 
are small, situated in the middle between the epimera of the fourth pair of legs 
and the abdominal margin, and touch each other at their inner angles; each plate 
bearing five large and two small stigmata. 
Found in ponds in the vicinity of the city of Guatemala. 
Var. ypsilon. (Tab. IX. figg. 1-1c.) 
Corpus ovatum, pellucidum ; macula dorsuali magna nigro-fusca, granulosa; glandula dorsualis lutea, Y-formis, 
integra. Lamine genitales pentagons, parvule, angulis internis se invicem tangentes, stigmatibus quinis 
vel senis instructs. Pedes atque palpi sicut in typo. 
Long. 0:25 millim. 
Hab. GUATEMALA, near the city (Séol/). 
Body ovoid, transparent, with a large brown dorsal patch, which is divided by an 
orange-coloured Y-shaped dorsal gland into three distinct spots. Genital plates penta- 
gonal, touching each other at their anterior angles, each bearing five or six large and 
two small stigmata. Legs and palpi as in the type. 
Found in the same pond with the type in the vicinity of the city of Guatemala. 
I cannot consider this little Atax specifically distinct from <A. septem-maculatus, 
with which it agrees in the colouring, in the shape of the legs and palpi, and in the 
character and size of the genital lamine. It differs from typical A. septem-maculatus 
in being a trifle smaller, and in the form of the sharply marked, non-ramified dorsal 
gland. 
3. Atax dentipalpis, sp.n. (Tab. X. figg. 1-1 d.) 
Corpus ovatum, fere rotundum, depressulum, pellucidum, flavo-albescens, postice tuberculis duobus setigeris ; 
macula dorsualis nigra, lata, per glandulam dorsualem brunneam, albo-marginatam, longam, antice bifur- 
