Miscellanea Zoologica. 371 



There has 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 

 (arancce.) The impropriety of mixing them in this manner with 

 the terrestrial Phalangia was soon perceived ; and Otho Fabricius 

 separated them, assigning the name Pycnogomim (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 

 Pycnogonidee, 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 

 Pseudo- 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 Agnathonia — ^-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 Trachearias, 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 Pycnogonidee should form a particular order, intermediate to 

 the Arachnides and the apterous parasitical insects. — Reg. Anim. iv. 277. Fam. 

 Nat. du Regne Anim. 318. 



f Hist. Nat. des Anim. s. Vert. v. 72. 



