SILPHIDAE. 521 



This most nearly resembles the female of 7. separatus (3838) from Mount 

 Hutt, but is distinguishable by the obvious thoracic impression, narrower 

 head and differently formed posterior tibiae. 



Length, 2| mm. ; breadth, quite 1 mm. 



Pakuratahi, near Wellington. One, taken from leaf-mould by Mr. H. W. 

 Simmonds ; 2nd January, 1915. 



Isocolon Broun. Man. N.Z. Coleopt., p. 1070. 



4042. Isocolon frontale sp. nov. 



Compact, oval, moderately convex, nearly glabrous, with a few fine, 

 indistinct setae along the slender lateral margins, nitid ; light castaneous. 

 the labrum, forehead, and apical portion of elytra flavescent ; antennae, 

 legs, and tarsi obscure rufous, terminal tarsal joints paler. 



Head as broad as thoracic apex, narrowed before the eyes, finely and 

 irregularly punctate ; forehead finely margined and rather deeply incurved, 

 the enclosed space pale testaceous and truncate in front. Eyes large, 

 transversely oval, not prominent. Thorax nearly twice as broad as long, 

 gently narrowed anteriorly, base truncate, with almost rectangular angles, 

 the apex slightly sinuate behind the eyes, its angles obtuse ; disc distantly, 

 irregularly, and rather finely punctate, a few punctures on the basal half 

 more distinct than the others. Scutellum smooth, broadly triangular. 

 Elytra nearly thrice the length of thorax, of the same width as it is at the 

 base and closely applied thereto, gradually narrowed posteriorly ; sutural 

 striae well marked nearly to the apices, their serial punctation rather close 

 and distinct, less so behind ; interstices plane, distantly and very finely 

 seriate-punctate. 



Tibiae distinctly expanded towards the extremity, spinulose externally, 

 the anterior with about three fine spines only, but an additional and stouter 

 one projects from the outer extremity. Basal three joints of front tarsi 

 moderately dilated, penultimate very small but not discernibly bilobed. 



Antennae stout, basal joint no longer than the next, third more elongate, 

 fourth shorter, fifth and sixth short and moniliform ; seventh, ninth, and 

 tenth abruptly enlarged, transversely subquadrate, eighth very short, 

 scarcely more than half the width of contiguous ones, the terminal conical. 



This resembles the North Island species I. hilaris (1912) in most respects, 

 but differs considerably in coloration; the enlarged antennal joints are 

 hardly any darker than the others. An examination of the frontal portion 

 of the head will at once lead to its identification. 



Length, 2^ mm. ; breadth, 1 J mm. 



Mount Algidus, Canterbury. One example only, found by Mr, T. Hall 

 on the 3rd December, 1913. 



4043. Isocolon modestum sp. nov. 



Oblong-oval, only moderately convex, nitid, with fine lateral margins 

 and a few inconspicuous setae alongside ; fusco-testaceous, the head and 

 middle of thorax piceo-fuscous ; mandibles, legs, and basal half of antennae 

 rufescent, remaining joints nigrescent and slightly glossy ; tarsi somewhat 

 rufo-testaceous, their last joint and the palpi paler. 



Head short, slightly and widely emarginate in front, with a groove 

 alongside each eye but without distinct punctation. Thorax subtruncate 

 at base and apex, the breadth about double the length, slightly narrowed 

 towards the front, with obtuse angles ; disc with a few scattered, unequal, 



