THE MYRIARODA OF NORTH AMERICA. 



207 



Genus SPIROBOLTJS. 



Scuti priuii latera brevia, haud produota. Scuti secundi latera longe produota, cum superfieiebus anticis tri- 

 angulis. 



Sides of tbe first scutum short, not produced. Slides of the second scuta very much produced, with anterior 

 triangular surfaces. 



SPIROBOLUS, Brandt, Recuoil, p. 114. 



The form and general appearance of this genus is very different from that of the true 

 lulus. The great size and thickness of the body, and the peculiar way in which the head 

 is set into it, so to speak, attract the first glance of the observer. The head is generally not 

 proportionally very large. The antennae in our American species (except angnsticeps 1) 

 arc very short, and often lie almost hidden in a groove in the side of the head, bent so as 

 to form a right-angled " knee," with their free end directed downwards. 



The eye-patches arc of various shapes, and, though large, are generally not very promi- 

 nent. The first scutum is broad, antero-posteriorly, with its sides more or less obliquely 

 truncate. The second scutum has its sides much produced and bent forwards, so as in a 

 measure to embrace the first scutum. Where it abuts against the head there is on each 

 side a triangular surface. 



In all the species which I have examined, the male appendages are formed after one 

 very pecidiar type, with marked specific differences in the minutise of their forms. This 

 may prove to be generic. In the true lulus no appendages have as yet been described 

 agreeing with this pattern. 



8. MARUINATUS. 



S. saturate brunneus, rubeo annulatus; capito copiosc minute punctata, antico punctorum maximorum serie 

 instructo; segmentis 53 — 57; scutis copiosc minute punctatis; squama analc triangula. 



Deep brown, annulate with red; head copiously minutely punctate, furnished anteriorly with a series of large 

 puncta; segments 53 — 57; scuta copiously minutely punctate; anal scale triangular. 



Iulus maroinatus, Sai/, Jouru. Acad. Nat. Sci., 1st scries, vol. ii, p. 105. 

 " " Gervaitt, Aptoros, vol. iv, p. 180; Kxped. L'Amcr. du Sud (Castelneau), Myriap., p. 10. 



" « Brandt, llecueil, p. 89. 



S. MAROINATUS, Newport. 



'I Iulus Amkricanus, Pal. Beauvois, Insect. Afrq. ot Amer., p. 155. 



? Iulus INOERTCS, Brandt, Eeoueil, p. 121. 



Iulus ornatus, Girard. 



? Iulus atratus Girard, Marcy's Report, Expl. Red River of the South, p. 274. 



