BIOLOGIA CENTRALI-AMERICANA. 
ZOOLOGIA. 
Class ARACHNIDA. 
Order ACARIDEA. 
Suborder I. ACARINA-TRACHEATA, Kramer. 
Fam. TROMBIDIDA. 
[Kramer, Grundziige zur Systematik der Milben, in Arch. fiir Naturg. xliii. p. 226 (1877). ] 
TROMBIDIUM. 
Trombidium, Latreille, Gen. Crust. et Ins. i. pp. 144, 145 (1806). 
1. Trombidium mexicanum, sp. n. (Tab. I. figg. 1-1 d.) 
Corpus oblongum, pyriforme, depressum, postice rotundatum, tomentoso-hirsutissimum ; tomentum e pilis 
quadrifidis sistens, colore uniformi coccineo, ex sericeo nitente; superficies dorsualis impressionibus trans- 
versalibus induta. Pedes breviusculi, coccineo-sericei, tomentosi; subtus (exceptis tarsis) pilis longis 
pinnatis in seriem dispositis instructi. Palpi longi, marginem corporis anteriorem superantes ; pilis tomen- 
tosis pinnatis induti; appendicula lobiformi lanceolata, haud lata, longe pilosa. Mandibule fusiformes, 
ungue falciformi acuto armate. Oculi coccinei, in tomento fere absconditi. 
Long. 5-6, lat. max. 4 millim. 
Hab. Mexico, Presidio (Forrer). Two examples. 
Body oblong, pyriform, depressed from above and below; shoulders protracted 
between the coxe of the second and third pairs of legs; posterior part of the 
body cylindrical, its hind margin rounded; dorsal surface with a few transverse im- 
pressions; colour uniform, a bright scarlet; the whole body thickly covered with 
velvety, quadrifid hairs. Coxe of the second and third pairs of legs separated by the 
protracted shoulders. Legs rather short, when compared to the mass of the body, of 
about equal length, the anterior ones a trifle thinner and longer than the others; 
slightly compressed, higher than broad, thickly covered with short red hairs which give 
them a whitish silky lustre; beneath bearing brushes of long, straight, pinnate hairs, 
which in the fore legs are but imperfectly developed and limited to the first three 
joints (counting from the coxa); the brushes are wanting from all the tarsi; front 
tarsi obliquely truncate at the top, their lower surface covered with very short hairs 
which are arranged into a sort of tactile brush, their claws much smaller than those 
BIOL. CENTR.-AMER., Arachn. Acar., December 1886. B* 
