COLLEMBOLA OF MINNESOTA 37 



b. — Color blue of purple. 4. 



3. a. — With two rounded eyespots, 10 ocelli, antennae blue. 



decemoculatus, 85. 



b. — With four eyespots, the anterior ones each containing 



two ocelli; the posterior ones, one each. Antennae white. 



sexoculatus, 86. 



4. a. — Color dark purple ; with legs, top of head, and bases of 



antennae brownish yellow. purpureus, 87. 



b. — Color blue and white. Antennae entirely blue. 5. 



5. a. — Rather blackish blue with five white seginental cross- 



bands. Head entirely blue, antenna; dark blue, concolor- 

 ous throughout. Tibiae blue. aenescens, 89. 



b. — Rather a clear blue, without noticeable white cross- 

 bands. Head rather light on top. Antennae light blue at 

 base, gradually becoming darker distally. Tibiae clear. 



pusillus, 88. 



Family Poduridae. 



The family Poduridae is a large one and seems to occupy a 

 position somewhat lower than the Entomobryidae. Its genera 

 show rather less specialization, or perhaps, as seems to me, thev 

 show the specialization of reduction. Among them we fail to 

 find any of the long, slender antennae modified for tactile uses. 

 To be sure, many have curious sense bulbs at the ends of the 

 antennae, but such modifications as ringed antennae are altogether 

 unknown. In most cases the typical four-jointed antenna i=; 

 found in its simplest form. The claws show reduction. In some 

 genera the inferior claw is absent, while in others it is reduced 

 in some species to little more than a bristle. In others, again, 

 the claws are both well developed. The forms are mostly low 

 and more or less flattened, which necessitates a short ventral 

 tube in most cases. The furcula is generally short, sometimes 

 so short as to make it difficult to determine whether a species 

 is a Podurid or an Aphorurid. On the other hand, the gulf be- 

 tween some of the lower Isotomas and the Poduridae is not so 

 great as some of the older collembolists supposed, basing their 

 conclusions upon the forms then known. "Furcula on the 

 antepenultimate (fourth) abdominal segment," used always to 

 mean a Podurid, but now a few Isotomas are known of which 



