Miscellanea Zoologica. 371 
There lias been, and there still is some diversity of opinion among 
naturalists relative to the place which this family ought to occupy 
in the " Systema Naturae." Linnaeus placed the only two species 
with which he was acquainted in the genus Phalangium, a kind 
of land spiders standing between the mites (acari) and true spiders 
(aranece.) The impropriety of mixing them in this manner with 
the terrestrial Phalangia was soon perceived ; and Otho Fabricius 
separated them, assigning the name Pycnogomtm (previously used 
by Brunnich) to the marine species. He was followed by Muller, 
the discoverer of some additional species. Fabricius, the entomolo- 
gist, divided all that had been made known previous to his time into 
two genera, viz. Nymphon and Pycnogonum ; and Latreille, his im- 
mediate successor in the throne of entomology, was at first of opi- 
nion that the peculiar characters, especially the tubular mouth of the 
Pycnogonidae, justified him in elevating them to a distinct order 
among his " insecta acera," which includes the myriopods, spiders, 
and mites. He afterwards saw reason to degrade them from this 
rank to that of a " family," which he located, after Linnaeus, between 
the phalangoid spiders and the mites. He created a new genus 
(Phoxichilus) for the reception of a species which would not har- 
monize with those already characterized.* In Lamarck's system, 
which proceeds from the less perfect to the more complex animals, 
the Pycnogonides are found in the second order of his Arachnides, 
characterized by their want of antennae, by breathing through 
branched not ganglionated tracheae, and by having two or four simple 
eyes. They follow, and are consequently considered superior to the 
mites and Phalangia ; but being associated in one section with the 
Pseu do- Scorpions they are to be considered coequal and affined to 
them,t a conclusion than which nothing can be more erroneous. Dr 
Leach, in his first essay, published in the Edinburgh Encyclopedia, 
made of these animals an order amongst the Arachnides, which he 
named " Podosoma," and which he divided into two tribes, Gna- 
thonia and A gnathonia -characterized by the presence or absence 
* The changes in their relative position which Latreille subsequently made 
are immaterial. In the Reg. Animal, they constitute the second, and in his 
" Families Naturelles" the first family of the Arachnides Tracheariae, following 
the Pseudo- Scorpions and preceding the Phalangia and mites, a station of the 
goodness of which he very properly expresses his suspicion ; and he afterwards 
suggests that the Pycnogonidae should form a particular order, intermediate to 
the Aracbnides and the apterous parasitical insects. Reg. Ariim. iv. 277. Fam. 
Nat. du Rcgne Anim. 318. 
f Hist. Nat. des Anim. s. Vert. v. 72. 
