Cephalothorax 7 



the antennse, as has been indicated already in a few words by Simon (6, p. 117). This piece 

 is found, for instance, in the shape of a short and rather broad plate in Toinicomerus Pav., 

 Sabacon E. S., and Farasabacon, but it is wanting in Ischyropsulis, Taracus and Sclerosoma. 

 In those Phalangioidai whose integuments are comparatively soft, the collar is but little 

 developed and so much the less conspicuous as it is often placed on the anterior extremity 

 of cephalothorax under the anterior margin of the dorsal shield; but in Phalangioida? with 

 harder integuments, such as Phalangium j^ropi-nquum Luc, and Ph. cirtamim C. L. Koch, 

 the collar is conspicuous in the shape of a transverse piece of chitine which is situated 

 above the base of antennse, and somewhat bent downwards; it shows here a longitudinal 

 groove along the middle and is continued downwards as a narrow strip between the antennae. 

 In Gagrella Thor. and allied genera we find either one such piece, as in G. Few Thor., or 

 three pieces, as in G. ndnax Thor., a small portion on either side being separated from the 

 main part in the middle, by an extremely fine groove in which the skin is soft^ In 

 Nemastoma there are known to be three pieces. In TroguloidiB they are discovered with 

 some difficulty because, like the antennae and the dorsal parts of the mouth, they are con- 

 cealed by the ocular tubercles or by the processes of the ocular tubercle. In Trogulus 

 and Dicranolasma they are very well developed. In Trogulus rostratus Latr. the middle 

 part is a large pentagonal piece, whilst the lateral portions are very small. In Dicrano- 

 lasma^, on the contrary, the middle portion is rather small and has the form of an equi- 

 lateral triangle, whilst the lateral pieces are somewhat larger. The position of these pieces 

 in Palpatores is somewhat varying, principally in accordance with the shape of the anterior 

 extremit}- of cephalothorax. In Troguloidfe their position is perjjendicular, but it is slanting 

 in the majority of Phalangioidte and in Nemastoniatoitke. In the former of these two groups 

 they frequently carry a pair of protuberances which stand close together and which are 

 particularly well developed in Gagrella and allied genera. In Gagrella and congeners the 

 pieces in question seem to have a tendency to assume a position in continuation of the 

 dorsal shield, and in Nemastoma they do so altogether; in Fantopsalis E. S., which is dis- 

 tinguished by enormously long antennaj, the collar simply coalesces with the anterior border 

 of cephalothorax, but may be discerned by the longitudinal groove in the middle which is 

 found in this genus, as in all Phalangioidse where this piece is (or these pieces are) well 

 developed. 



Simon has pointed out (b, pp. 117 and 267) that in Ischyropsalis a small piece of the 

 'lateral margin on either side remains independent and separated from the rest of cephalo- 

 thorax by a narrow strip of soft skin. On these " pieces epimeriennes " (an appellation which 

 does not appear to us very happy) the openings of the stink glands are situated, but 

 they do not appear as independent pieces in Taracus E. S., Toinicomerus Pav.', Sabacon E. S., 

 or Farasabacon n. gen. Vestiges of such independent pieces are frequently seen in Laniatores, 

 a groove which only diverges a little anteriorly being often visible near the lateral border 

 of cephalothorax (" limbus lateralis" W. S.). In Cj'phophthalmi no vestiges are traceable of 

 such " pieces epimeriennes." 



' Leiobiiiiiiiii, which upon the whole approaches GngreUa spect, as in others, the structure observed in G'l/as E. S. and 



and its relatives, does so also in this point : the piece of Prosalpia L. Koch, shows that these genera are not nearly 



chitine in question agrees essentially with that in Gagrella allied to Leiobtinum. 

 Fett as to shape and degree of development, though it is less - An uudescribed species from Sicily, 



firmly chitLnized and occupies a lower position. In this re- ■• Pavesi is of opinion that they exist in Tomkoments. 



