236 Zoology of Colorado 



pendra heros of Girard. It is rather common near the eastern 

 base of the mountains, as in the vicinity of Boulder. It was 

 taken at Rocky Ford by Burt E. Warren. In houses (on one 

 occasion in the main building of the University of Colorado), 

 running about the walls in search of flies, may occasionally be 

 found a singular centipede with extremely long legs. This is 

 the Scutigera forceps of Rafinesque, not really a native of Colo- 

 rado, but introduced from the south. Under stones the reddish- 

 brown Lithobiidae are very abundant, and the long thread-like 

 Geophilidae are sometimes found. There are several native 

 Lithobiidae, which have been discussed or described by Dr. 

 Chamberlin. In his latest paper (1925), he describes a new species 

 Neolithobius suprenans, which was first collected in Colorado by 

 members of the Hayden Survey in 1873, but has had to wait 52 

 years to be made known. Nadabius coloradensis is one of our 

 common forms; it is 12 to 16 mm. long when adult, and has the 

 angles of none of the dorsal plates produced. Pokabius pungonius 

 was found at Marshall, and has never been detected anywhere 

 else. Some years ago I found the European Lithobius forficatus 

 of Linnaeus (certified as such by Chamberlin) in Boulder. It has 

 of course been brought in accidentally by human means. In 

 Europe it is extremely common; I collected it at Southwater, 

 Sussex, England, and Wangen, Baden. 



There is still much to be done on our millipedes and centi- 

 pedes, and no doubt many species await discovery. There has 

 never been a special student of these groups in Colorado. 



TICKS AND MITES (ACARINA) 



Ticks are really gigantic mites, mostly living on and at the 

 expense of warm-blooded vertebrates. The species are not very 

 numerous, but they make up for this in the abundance of in- 

 dividuals. The only kind which is particularly noticeable in 

 Colorado is the common wood-tick, which is a source of annoyance 

 to camping parties and strollers in the woods during the earlier 

 part of the summer. This is the tick which has long been known 

 in Montana as the transmitter of the organism causing Rocky 

 Mountain spotted fever, a very deadly disease. In recent years 

 spotted fever has spread southward into Wyoming and Colorado, 



