312 NATURAL IIISTOUY OF ARTHROPODS. 



them, insuring their destruction as soon as tlie eggs hateli. Tlie full-grown hirvae 

 have a similar form to that of Ilipjiodainiu convevgens, are hlack, with a yellowish 

 spot on each side of the first, and another on the dorsum of the fourth abdominal 

 segment. When ready for pupation the larva attaches its abdomen to some ob- 

 ject, shortens and swells itself up so as to split its larval skin, and, thus freed from 

 it, appears as a jnijia in new colors and form. The spotted })uiia, for the most 

 part black and pink, is likewise similar to that of Ilippodamia convergens. The 

 imago, after it emerges from the pujja is, for the most l>art, very soft, and pale 

 yellow, but it becomes quickly harder and darker-colored. A. bijninctata is espe- 

 cially abundant duiing the latter ])art of sunnner and in autumn on birch trees, 

 probably attracted to these trees by the plant-lice which during that jiart of the 

 year abound on birches. 



Another genus, Ilippodamia., contains sjiecies that are more elongated than those 

 of CoccineUa, and a inunber of them are common in the United 

 States. II. convergens and //. tredechnpunetata are known to 

 devour the eggs of the Colorado potato-l)eetle, while on the 

 Pacific coast H. ainhigua is also of economic value. Megilla 

 inacidata, which has a similar form and is often mentioned as 

 Fig. »i9. - Hippodamia ^ IUppodamia, besides eating plant-lice, preys extensively on the 

 conren/em; «, larv.a; ehiuch-bug, and also eats the eggs of the Colorado viotato-beetle. 



Oj pupa. ^' ^^ 1 



Its eggs are similar to, l)ut smaller than those of the jjotato-beetle 

 and might be mistaken for them. 



Ejnlachna borealis, the northern lady-bird, which is honey yellow with black spots, 

 was supposed for a long time to be the sole North American species of this family 

 which was a vegetable-feeder. The larva; of this species feeds uj)on gourd, squash, 

 and pumpkin vines, and the imago eats the same food. The larva is yellow and is 

 clothed with black-tipped sj)ines. The corresponding Eurojiean s]jecies, E. glohosa 

 and E. wtdecinunaodata, are jihytophagous, the former often doing considerable 

 damage to lucern, and now and then eating other plants, while the latter attacks 

 bryony. 



To the family Endumvchid.e belong nearly four hundred described species which 

 live, both as larva and imago, ujion fungi. The species are distinguished from the 

 lady-birds by their cylindrical pal])i and long antenna;, and often by their prothorax 

 having grooves at its base, and by their elongated head, the lady-birds having groove- 

 less prothora.\ and short head. The tarsi are manifestly four-jointed in some genera 

 of Endomychidae. The species are numerous in the trojjics, many species being found 

 in Brazil, where, according to H. W. Bates, they hold a sort of complementary rela- 

 tionship to the Erotylida', — another fungivorous family, the species of which closely 

 resemble Endomychida', although the sjiecies of the former family mostly have 

 cryptopentamerous tarsi, — in that the Endomychidre devour small fungi w'hile the 

 Erotylida^ live upon large ones. The species of both families are slow in -^^- 

 their motions and some of them are gregarious. 



Mycetina vittata, one of our most common species of Endomychida', 

 is flattened, reddish-brown in ground coloration, with the sutural oi- 

 median ])ortion of the elytra black, and with a black stripe along the no. 350. — li/yce- 

 middle of the outer j>ortion of each elytron. This species is often found, 

 in grou])S of a few to a hundred scmi-torjiid sjjccimens, under half-decayed stumps, 

 or more rarely under boards, about mid-winter in New Enghnul. 



