in 17 Osmia-species of the adunca-GVowj.?. 165 



others. Still I. do not mean that I would propose to classify 

 the Group according to these characters only. 



We may now proceed to consider my Figures of this 

 segment in the several species examined by me. In each 

 case, after describing the segment, 1 shall say what I con- 

 sider the species possessing it to be, and where necessary, 

 shall give reasons for my belief, and mention other specific 

 characters of the insects under consideration. 



I shall then add a separate note on the synonymy of four 

 especially puzzling species, and lastly give Diagnoses of 

 four other species of which I have been unable to find 

 descriptions, so that I am obliged to treat them as " new." 



Fig. 1. The main lobes are rather angular laterally at 

 the apex, but unspined ; their apical margins run only a 

 little obliquely : the tooth-like hair pencil in the groove 

 which separates them is conspicuous. 



The basal part of the process is not petiole-like, but very 

 wide and almost rectangular. Before its apex are a pair 

 (near together) of conspicuous tubercles each emitting a. 

 strong pencil of erect long hairs. The apex itself run's out 

 suddenly into a sort of long narrow spine, which laterally 

 (Fig. ]a) is seen to be much deflexed. 



This species is, I believe, universally accepted as the 

 true adicnca, Latr. 



It is characterized by its black calcaria, shining some- 

 what naked dorsal segments, the form of its antennas, etc., 

 and also in the $ (a character as yet, I believe, unnoticed), 

 by the production of the last ventral segment at its apex 

 into a triangular, somewhat reflexed, spine. 



I have examined specimens from all parts between 

 Algeria and the Sea of Marmora, which completely agree 

 in the characters given above, and with the descriptions of 

 all authors consulted by me. 



Fig. 2. The main lobes have rounded apices and their 

 margins run diagonally. Central hair pencil hardly 

 developed, and pilosity altogether short and thin. 



The process is nearly triangular, with no tubercles or 

 pencils as in adunca. Its apex is drawn out gradually into 

 a spine ; first deflexed, then again reflexed and a little 

 dilated (Fig. 2a). 



The specimens before me are some of those I took in 

 Syria and Asia Minor in the spring of 1889, which have 

 been described by Friese (Entom. Nachricht.) under the 

 name lysholmi. 



