ABSTEACT. 



In 1892 the renowned Swedish Arachnologist, T. Thorell, published a small paper in 

 which he gave the first elaborate description of a species of the genus Cryptostemma, which 

 is one of the main types of recent Arachnids. Before Thorell — who had only one old specimen 

 of his species — two other sjjecies had been established, one by Guerin, the other by Westwood. 

 Thorell followed earlier writers in referring the family Cryptostemmatoidis Westw. to the 

 order Opiliones, but he also established the type as a suborder and gave a key of the 

 distinctive characters of the four suborders of that order. Two of these suborders, Palpatores 

 and Laniatores, are very rich, each comprising a great number of genera with more than 

 one hundred of known species ; to Palpatores belong nearly all forms of European Harvestmen. 

 The two other suborders are small, and animals belonging to them are scarce in all Museums. 

 It may be stated at once that our paper deals with the whole order Opiliones in the sense 

 of Thorell ; and our treatment of his two small and hitherto very imperfectly known suborders, 

 Cyphophthalmi (Anepignathi, Thor.) and Ricinulei (the family Cryptostemmatoidas), is as 

 complete as to morphology, anatomy, and classification as the material at our disposal allowed 

 us to make it. But we at once perceived that Karsch was in the right when, in 1892, he 

 removed the Cryptostemmatoidse from the order Opiliones ; we have established that family 

 as a separate order, adopting for it the name Ricinulei, proposed by Thorell for his suborder 

 of Opiliones comprising the same animals. The order Opiliones in the sense of Thorell 

 and earlier writers is therefore here dealt with as two orders, Ricinulei and Opiliones, which 

 are even very remote from each other. We had long been well acquainted with the two 

 large suborders Palpatores and Laniatores, but our .study of Cyphophthalmi gave rise to 

 further investigations of numerous genera of both these groups, our purpose being to 

 elucidate as completely as possible the differences between the three suborders adopted, 

 and secondly to point out features which proved themselves to be of systematic importance 

 in other respects. We give therefore a revision of the morphology of the dermoskeleton of 

 Palpatores and Laniatores, the anatomy of their sexual organs, etc., and the distinctive characters 

 of the families constituting the suborder Palpatores. 



Our material of the order Ricinulei and the suborder Cyphophthalmi has been comparatively 

 very rich — many times larger than that of any earlier author. When we began our study we 

 applied ourselves to all sources where, in our judgment, it might be possible that material 

 existed, and almost ever3^one has helped us as much as possible, lending us, or sometimes 

 presenting us with, rare forms. 



We .shall attempt to give a short summary of the paper, but it must necessarily be rather 

 imperfect, especially that part of it on Opiliones. It may be convenient to begin with the 

 order Ricinulei. Of that group onlj' three species had been named, each established on a 



