404 REPORT ON ZOOLOGY, MDCCCXLIV. 



or circulation. Respiration undoubtedly takes place through the skin ; the 

 movement of the fluids is completely irregular. A liver is not found, 

 perhaps it is represented by a granular mass at the ends of the processes of 

 the stomach. Such being the structure, the author regards the Pycuo- 

 gouides as phlebenteritic Crustacea. But the relation appears in another 

 light when we view the Pycuogonides as Araclmida. In this case the form 

 of the alimentary canal is nothing b\it what is ordinary in the class, for the 

 processes of the stomach are not only found very generally in Acari, 

 Phalangia, Araneidae, but in the last-named they are formed as in the 

 Pycnogonides, only their ends are here turned up instead of entering the 

 legs, a difference which is accounted for by the relative capacity of the 

 fore trunk and of the legs. 



Kroyer (Naturh. Tiddsskr. N. R. i, 90) has published an essay of great 

 importance, upon this order, Bidrag till Kundskab on Pycnogoniderne eller 

 Sospindlerne. 



It is divided into three parts. 1. General remarks on the comparative 

 anatomy, &c. This part contains much important matter, in particular the 

 notices of their habits are interesting. The Pycnogonidse are extremely 

 sluggish, they represent the sloths among articulated animals. Many of 

 them keep close to land, and on the northern coasts Pycnogonurn littorale 

 and Phoxichilidium femoratum are found at low tide lying motionless under 

 stones. Others occur in deep water on tangle and polypus stems, which 

 some of them resemble in colour, as the species of Nymphou and Pallene. 

 In general they are solitary, only Pycnogouum littorale is found on the 

 northern coast in families or larger societies. According to various authors, 

 their food consists of marine animalcules, which they seize with their 

 pincers ; on this head the author has obtained no satisfactory evidence. 

 Not uncommonly he has found Pycnogouum littorale at the foot of Actiniae, 

 as if endeavouring to insinuate itself between them and the rock, and he 

 coniectures that their food consists of the mucus which is secreted abun- 

 dantly by the Actiniae. At the same time the Pycuogonum is often found 

 in the stomach of the Actinia. Latreille's statement that the Pycnogona 

 live upon whales, arose from their having been confounded with a different 

 animal. The Pycnogonidse seem to be diffused through the entire ocean, at 

 least they are found from Spitsbergen to Rio Janeiro, at the Cape, and 

 about New Holland. 



2. Characters of the genera and species. Zetes, a new genus : the outline 

 of the body nearly oval ; the snout very large, three-jointed ; mandibles 

 without pincers, teu-joiuted maxillae, the egg-carrying feet also ten-jointed 

 (found in both sexes), the legs short without subsidiary claxvs ; the abdomen 

 of two segments. One species, Z. Mspidus, from the southern coast of 

 Greenland. Besides this, accurate descriptions are given of Nymplion 



