(i.N THE CIIILOPUDA OF NORTH AMERICA. I I 



Fain. V. GEOPHILIDiE, Loach.* 

 ngula subsegmentis duobus completis sed insequalibus efforniata, el pedum par 

 unicum geretitia. Oculi nulli. Antennas 14 articulates. Pedes anales breves, styliformes. 



The family character of this group, which first attracts attention, is the large number 

 of segments, each of which is composed of two unequal subsegments. The boundaries 

 ' of the respective scuta of each pair of the latter are well marked by sutures. &c., but 

 the sterna are completely consolidated. The head varies in form, size, &c., and fur- 

 nishes the principal generic characters. The number of joints of the antennas is fixed 

 tor the family, hut nevertheless good specific, ami even generic, characters are derivable 

 from these organs. The mosi important specific characters besides those before 

 alluded to are founded upon, firstly, the peculiarities as to size, shape, proportion. &c., 

 o[' the component portions of the head and its appendag ondly, the color ami 



form of the body and the number of segments composing it ; thirdly, the structure of 

 Legs, especially of the last pair; and. finally, the markings and suture- of the scuta 

 and sterna. We have never had an opportunity of examining large suites of speci- 

 mens, so as to determine as to the constancy of the various characters enumerated, 

 hut they probably do not vary a great deal. 



Gen. 1. MECISTOCEPHALUS, Newp.f 



mentum cepbalicum elongatum, angustum, latitudine plus duj Antennae approximates, 



articulis obconicis. Subsegmentum prebasale sejunctum Bed basale subbasaleque coalita. Mandibular 

 magnse, intus denticulate. ( Fig. 

 M. 11 i, \ i s, n. sp. — M. fulvus, politus; capite dilute aurantiaco, punctato, pilis longis rigidis paucie ; seg- 

 mento cephalico antice truncato, postice illieo angustato et vis truncate; antennis longis, pilis longis 

 rigidis multis; labio profunde punctato, antice euiarginato, medio sulco impresso; mandibulis distincte 

 punctatis, pilis rigidis paucis, quadridentatis ; segmento anali piloso; pedibus pilis longis, paribus 57. 

 ophilus an -ay, Jouru. Acad. Nat. Sci. 1st series, vol. ii. 



Cephalic segment scarcely narrowed at all. except at the posterior end, where it is 

 rapidly contracted, being indeed rounded oil'. Body slender and polished. 

 Scuto-episcutal and sterno-episternal sutures very distinct, as well as those 

 between the primitive -tenia. We have found this species around Phila- 

 delphia, although not very abundantly. They appear to affect the inner 

 bark or liber of decaying logs, especially that of the locust. (Robinht pseuda- 

 caeia, L.) We have, however , occasionally observed them under stones. It Fig 9 

 may possiblj be Geophilus attenuatus, but that species can never be determined from 

 Saj 's description. 



M. MELANONOXT S, n. sp. — M. parvus, gracillis, dilute aurantiacusj lineis duobus dorsalibus, Iatis, nigris, 

 e capite ad segmentum pcnultiniuni ductis ; capite dense minutissimc punctato, sparse breve pilosis; 



I. inn. Trans, xi. |"Proc. Zool. Soc. Dei L842, p L79 



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