24 Abdomen. Limbs 



sub-order Cyphophthalmi. In Taracus E. S., Tomiconierus Pav., Sabacon E. S. and Parasabacon 

 n. gen., there is behind the seventh sternite a well-developed plate which on the sides is 

 united to the eighth tergite. In Taracus this plate is besides in the middle fixed with the 

 seventh sternite, but on the sides it is separated from it by means of connecting skin. We 

 look upon this plate as formed — as in the other genera — by the fusion of the anterior ventral 

 piece with the lateral pieces of " corona analis." 



The result to which we thus have arrived is very different from the opinion set forth by 

 Wei.ssenborn (pp. 69, 70). " Tulk," says he, "counted ten dorsal arcs in Opilio Phalangium, but 

 only five ventral ones, separated by transverse grooves ; to which, however, sternum [operculum 

 genitale] must be added, which he reckoned as part of thorax. The latter represents evidently^ 

 the coalesced sternal arcs of the first five dorsal arcs, and carries the genital orifice at its anterior 

 margin." But Weissenborn knows evidently only the one genus Phalangium' out of the whole 

 order Opiliones, which is rather rich in forms, differing considerably from each other, nor is he 

 acquainted with the various publications, which treat of the morphology of Opiliones, not even 

 Simon's " Les Arachnides de France," which is so generally consulted. Indeed he cannot fairly 

 be said to know Phalangium or the writers to which he refers, Tulk and Balbiani. Had he 

 really known them, he could scarcely have failed to understand that the two tergites — the last 

 thoracic and the first abdominal one,— which Tulk describes as the two first tergites of abdomen, were 

 reckoned by Balbiani as belonging to thorax, which according to this view would have three 

 separate segments bearing limbs. That Weissenborn has not realised this is clear from his 

 utterances with reference to Balbiani, just before the passage quoted, viz. : " This observation 

 is nevertheless extremely interesting and important becau.se it shows that the Phalangides, at a 

 certain embryonic stage, exhibit a segmentation of cephalothorax, which is found permanently in 

 Solpugida?, and that they consequently pass through a Solpugidse-like stage in the course of 

 their development." Since this was written, a deviating opinion on the number of abdominal 

 segments has been advanced ; we do not, however, believe it necessary to disprove it, thinking 

 that our own view is solidly grounded. 



4. The Limbs. 



Antenme (chelicerEe) (PI. I., figs. 1/ — 1 f/ ; PI. IV., fig. 1 c) consist in Cj^hophthalmi as in 

 all Opiliones of three joints^ They are rather long, longer than in Laniatores and in the 

 majority of Palpatores^ The basal joint, particularly the proximal half of it, is quadrangular, 

 prismatic, and somewhat compressed. The inner side is as a rule fairly plane in part, and 

 forms most generally sharp corners with the adjoining sides, whilst the under side offers a 

 somewhat different appearance, and the upper and outer sides form rather rounded corners 

 between them. The upper side exhibits a transverse ridge in the middle or a little behind 

 the middle (PI. I., fig. 1 f, d), which shows just in front of the edge of cephalothorax; it is 



1 Italicised by us. importance to communicate on the subject. 



^ Besides which he professes to be aciiuaiuted with ■* Some genera of the.se latter possess long or even very 



"die Cyphophthalmiden," through the treatises of .Joseph long autenuee, such as the male of iJ/mHi;As7'«/<«s B. S. (which 



and Stecker. is said to be nearly allied to Acanlholophus), Ischijropsalis, 



^ We do not propose here to treat of antenna; in Laniatores Macropsalis W. S. and Paiitopsalis E. S., in which latter 



and Pali^atores, because we have no new information of genus they are several times longer than the body. 



