SCIENTIFIC SURVEY. 



161 



Insected as usual, while the abdomen is blunt, and a large saw-like 

 ovipositor projects from beneath.. They are among the largest of 

 hymeuoptera. Tremex colamba bores into beech trees. Urocerus 

 albicornis and another species is found on pines. Oryssus is a much 

 smaller genus with a slender ovipositor. There are but few species, 

 and they are found iu August flying about with a loud buzz. 



Tenihredinidoe, Saw-flies. We now come to a family whose af- 

 finities are closest to the Lepidoptera. In their bodies the three 

 divisions are less marked than usual, they only fly in the warmest 

 days, their larv^ have 18-22 legs, and closely resemble caterpillars, 

 and like them feed exposed on leaves. The flies are sluggish ; their 

 heads are transversely oblong, and the antennas are simple, club- 

 shaped or feathered. Their wings are folded at rest upon the 

 body, overlapping each other somewhat. Their ovipositors are 

 toothed like little saws, with which they bore into the stems and 

 leaves of plants to deposit their eggs. The larvee spin compact 

 cylindrical oval cocoons. They are found in companies on the 

 leaves of the alder and birch, holding on by their true legs while / 



the rest of the body is suspended and curved curiously upwards ; 

 or they occur as slimy slugs on the leaves of the pear and rose, 

 while others feed on the stems of plants, or construct cases of bits of 

 leaves to hide in, like Tineids, or roll up Fig. 9. 



a leaf like the Phyganidaj. The large 

 solitary larva of Ciinbex Americana is 

 found partially rolled up, on the elm and 

 birch. Lophyrus abietis (Fig. 9, female,^ 

 feeds on the fir. Selandria vUis and 

 rosce feed upon the vine and rose, and 



can be taken when those plants have leaved out. Many can be 

 taken early in summer about alders and willows. 



Lepidoptera. 

 Butterflies are easily distinguished from the other groups by their 

 knobbed antennas ; in the Sphinges and their allies the feelers are 

 thickened in the middle ; in the Moths they are filiform and often 

 pectinated like feathers. Lepidoptera have also been divided into 

 three large groups, called Diurnal, Crepuscular and Nocturnal, 

 since butterflies fly in the sunshine alone, most Sphinges in the 

 twilight, (many of them fly in the hottest sunshine,) and the moths- 

 are generally night-fliers, though many of them fly in the day time, 

 thus showing that the distinctions are somewhat artificial. 

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