NATURAL SCIENCES OF PHILADELPHIA. 289 



L. parietina. Brunneo-flavescens ; thorace vittis tribus fuscis, media capil- 

 lari ; alae nebulis, strigis et maculis pallide fuscis; stigmate pallido, longo ; 

 venula stigmaticali a venarum mediastinalis et subcostalis ter minibus ceque distant; 

 long. 0-6 65. 



Head, proboscis and palpi dark brown ; antenna? pale, joints of the flagellum 

 brown at the basis. Praescutura yellow, with three brown stripes ; the inter- 

 mediate is divided by a longitudinal, pale, sometimes hardly apparent line ; 

 the lateral ones are abbreviated before and extend over the scutum behind; 

 scutellum and metathorax brownish ; pleurae brownish, mixed with yellow ; 

 halteres infuscated, whitish at tip ; feet yellowish brown, a pale ring before the 

 tip of femora; the latter pale; tarsi brown. Abdomen brownish; posterior 

 margin of segments and a longitudinal stripe along the middle of the back, 

 pale. Wings with clouds on all crossveins and with pale brown irregular spots 

 in almost all the areae ; in three or four of the apical areolets these spots assume the 

 shape of an inverted V. The stigma is very long, pale ; the stigmatical crossvein 

 is in the middle of the distance between the tips of the mediastinal and the 

 subcostal vein ; the mediastinal crossvein is close at the tip of the mediastinal 

 vein. 



The position of the stigmatical crossvein, and the very oblong stigma dis- 

 tinguish this species from all the others of the group. Its antennae, especially 

 in the living specimens, seems to be 15-jointed, the linear part of the 14th joint 

 being unusually long ; still, a careful examination convinced me that there was 

 no articulation to separate this 15th joint. 



Trenton Falls, on fences, in September, numerous (J 1 and $ specimens, 

 (nob). 



L. hudsonica. Thorax vittis quatuor, alae fusco-maeulatas et nebulosae; 

 maculae in margine anteriore obscure brunneae, subopaecee; earum prima 

 duplex ; long. 05. 



Head cinereous above, yellowish-ferruginous below ; proboscis and palpi 

 brown ; antennas brown ; basal joints yellowish-ferruginous ; prffiicutuni with 

 four brown stripes ; intermediate ones separated by a yellowish line which is 

 gradually widened anteriorly ; halteres with a brown knob ; feet (?) ; wings 

 with brown spots and clouds; four deep brown spots along the anterior mar- 

 gin; the first is double, consisting of two spots, one at the base of the praebra- 

 chial area, the other immediately beyond it, connected together by the 

 expansion of the first of them in the pobrachial area; the second spot, at the 

 origin of the petiole, is trapezoidal, the oblique sides being slightly excised ; 

 the third, at the tip of the petiole, is oblique and double; the fourth, at the 

 tip of the subcostal vein is rounded ; the intervals between the three first of 

 these spots are cloudless, whitish ; the clouds on the remaining portion of the 

 wing are exactly like those of L. immatura, only their color is more intense ; 

 an undulated one runs across the apical portion of the wing, and there are 

 several along the posterior margin. The fork formed by the tip of the medias- 

 tinal vein with its crossvein, is like that of L. solitaria, that is, the upper 

 branch is longer and oblique, the lower one being short and perpendicular. 



Single female from the Slave Lake (Huds. Bay Terr.) by Mr. R. Kennicott. 



The resemblance between this species and L. immatura is very striking; still 

 they can be distinguished by some very reliable characters. The desire to 

 prevent their confusion induced me to describe this new species, although I 

 have but one imperfect specimen. The principal characters distinguishing 

 them are 1st, the spot at the base of the pra?brachial area is simple in L. imma- 

 tura, whereas it is composed of two successive spots, connected as described 

 above, in the other species; 2d, the structure of the mediastinal fork, and per- 

 haps, 3d, the brown knob of the halteres in L. hudsonica, whereas in L. immatura 

 the upper portion of this knob is pale. Besides, the spots of L. hudsonica are 

 of a much more intense brown, contrasting with the pale space between them. 



We have now five closely allied species within the genus Limnobia proper. 



1861.] 20 



