TRACHEATA 401 
and owing to the way the metasoma is usually carried, over 
the head, it can readily be injected into any prey which has 
been caught and held by the pedipalpi. 
The generative glands, like those of Limulus, consist of a 
network of tubules; these are hollow, and the cells lining 
their lumen give rise to the reproductive cells. The testes 
consist of two pairs of longitudinal tubules united by cross 
branches, on each side of the body; the efferent duct leads to 
the external opening on the first mesosomatic somite ; its distal 
end is modified to form an intromittent organ, and it bears 
accessory glands. 
The ovary is single, and consists of three longitudinal 
tubules united by transverse ducts; it les ventral to the 
liver, and is to some extent embedded in that organ. The 
ovary is situated in the mesosoma, and the oviducts run 
forward, one on each side, to open upon the genital operculum. 
The ova are formed by the growth of cells lining the tubules, 
and they project from the surface in the form of follicles. 
They are fertilised in situ, at any rate, in one species. After 
going through the early stages of segmentation, they pass into 
the oviduct, and there complete their developement. The young 
are born in a condition resembling their parents, the scorpion 
being viviparous. 
Ciass II. Pseudoscorpionida. 
CHARACTERISTICS.— The abdomen is not divided into meso- 
and meta-soma, but is broad and flat, and consists of ten or 
eleven somites ; the animals are all minute; they breathe by 
tracheae ; the pedipalpr are chelate. 
In many respects the Pseudoscorpions resemble minute 
scorpions, but their abdomen is not produced into a tail, nor 
does it terminate in a poison gland. They breathe by 
tracheae, which open externally by two pairs of stigmata 
situated in the third and fourth abdominal somites. Like 
spiders, they are provided with spinning glands, which lie 
partly above the liver in the prosoma, and which open at 
the tip of the moveable joint of the chelicerae. 
26 
