46 JAMES WATERSTON. 



deserves mention, viz., the very frequent failure of the second anterior medio- 

 dorsal bristle on the left side of the mid lobe. The lateral ridges of the propodeon 

 are really folds more or less internally strengthened. If preparations of Paraphelinus 

 are made too quickly, the thin mid-dorsal region of the thorax is apt to collapse 

 longitudinally, forming a more or less distinct furrow. This appearance can very 

 easily be produced by plunging a specimen into oil after incomplete dehydration. 

 Whether in life this line of weakness in the chitin has a sulcate appear eance or not 

 is uncertain, but I think the point worth mention, as Girault (6, p. 74) says of Para- 

 phelinus australiensis, " There is a narrow median grooved line down the thorax." 

 P. speciosissimus, Gir., is much more isolated, and it was hardly advisable to recon- 

 struct the genus, as Mr. Girault (5) has done, from such a form. In four of the five 

 described species the forewings are hyaline or faintly tinted, not conspicuously 

 banded ; the general coloration pale, not black and yellow ; and the eyes hairy, 

 not bare. Later Mr. Girault (9, p. 180) mistakenly, as it seems to me, sank Para- 

 phelinus : " The forms named Paraphelinus, Perkins, intergrade with the forms of 

 Aphelinus, Dalman, as the Australian species show, so that obviously there are not 

 two genera represented by them. Paraphelinus must therefore fall as a true synonym 

 of Aphelinus." 



In Aphelinus (sens, str.), which preys upon various Aphids, the head is short and 

 thin, normal, lenticular, with large eyes, behind which there is no temporal develop- 

 ment. The occiput is sharply margined where it joins the vertex. The genal keel 

 passes ventrally outside and behind the toruli ; the clypeus is practically in the same 

 plane as the f rons, and its edge is straight. The mid lobe of the mesonotum is densely 

 covered with short sharp bristles, the parapsides, which are deeply invaded by the 

 axillae, bear 4 bristles. There are short, stout bristles on the metapleurae. The 

 fore wings are triangular and the hind wings broad, with a short fringe ; the abdo- 

 minal tergites decrease in length posteriorly, and the ovipositor and its sheath are 

 short. In all these characters Aphelinus, Dalm., offers a precise contrast to Para- 

 phelinus, Perk. ; and there are other differences, less obvious but equally important ; 

 e.g., in Aphelinus instead of a backward-sweeping parabolic incrassation the pleurae 

 show a short nearly verticle anterior rib. The prepectora are medianly fused and, 

 in conjunction, band- or collar-like, reminding one of the genus Coccophagus, to which 

 Aphelinus also approaches in its mandibles (cf. also the mesonotum). The genotype 

 of Aphelinus is A. abdominalis, Dalm. (Svensk. Vet.-Akad. Handl., xli, p. 181, 

 t. 8, f. 55, 56, 1820), of which A. basalis, Westw. (Ann. Nat. Hist., vi, p. 122, 1833) is, 

 I believe, correctly regarded as a synonym. The foregoing remarks on the generic 

 characters are based on an examination of two very old specimens of A. basalis in 

 the British Museum Collection ; one bears the data — " stood under this name in old 

 B. M. Coll. — C. Waterhouse " ; the other is labelled " basalis " in the handwriting 

 of F. Walker, to whom the determination of both examples is due. The first is now 

 completely dissected on two slides, the second mounted whole, except that the fore 

 wings are under a separate cover- slip. 



But while Paraphelinus is distinct from Aphelinus, it is closely approached by the 

 small yellow-bodied group (at present placed in Aphelinus) which attack Coccids. 

 Whether Perkins' genus should include the latter or not I cannot say ; it is one of 

 the Coccid-destroyers, A, diaspidis, How. (Ann. Kept. Dept. Agric, p. 355, 1880), 



