SPHECID.-E. 97 



PASSALCECUS, Shuck. 



Species mucli resembling those of Diodoiitus in geueral 

 appearance but more elongate, the mandibles straight on 

 their exterior margin, the labrum produced and pointed ; 

 thorax twice, or nearly twice, as long as wide, the pro- 

 podeum elongate and finely reticulated; abdomen sub- 

 parallel-sided in the S> elongate oval in the ? , the second 

 segment slightly constricted at the base, apical ventral 

 valve in the c? with an upturned curved process, apical 

 dorsal valve in the ? without a pygidial area; posterior 

 tibia? without spines. Four sjiecies are recorded from the 

 British Isles ; they make their nests in pierced bramble 

 stems and decaying wood. 



(4) 1. Mesopleuraj witla two transverse crenatures 

 at right angles to the perpendicular one, 



(3) 2. Mesonotum simply punctured, anterior longi- 

 tudinal impressions simple, face with a 

 spine between the antennas . . . cokniger, 



(2) 3. Mesonotum coriaceous, anterior impressions 



crenate, face without a distinct spine . insignis. 



(I) 4. Mesopleurffi with only one transverse crena- 

 ture. 



(6) 5. Labrum and tubercles black .... gbacilis. 



(6) 6. Labrum and tubercles white'. . . . monilicoknis. 



P. COrniger, Shuck. (? nee c?) {insigms, Shuck., Smith, 

 cj nee ? ). — Black, tubercles yellow; mandibles, iJalpi, 

 and basal joint of the antenna; in front flavous in the (^, 

 testaceous in the ? , tibia?, tarsi and the extreme apices of 

 the femora testaceous, the posterior tibia> clouded in the 

 middle ; head and thorax finely punctured, somewhat 

 shining, the former with the vertex square, face below the 

 antennae with silvery hairs, between the autcnnte armed 

 with a sharp spine ; mesonotum with its lateral margins 

 crenate, in front with two impressed lines, not quite 

 reaching its centre, and with two smooth, slightly-raised 

 lines between them, dorsal lino narrowly impressed, im- 

 pression in front of the scutollum crenate, mesopleuno 



