INSECTA MADERENSIA. " 699 



Male, with the breast beneath (between the intermediate and posterior legs) widely impressed, and 

 more densely clothed with longer and somewhat fulvesceut pile. With the abdomen beneath 

 longitudinally impressed throughout the basal Jive segments, though only lightly so on the 

 ventral ones (the impression densely clothed with fulvescent pile except towards the apex, where 

 it is glabrous, highly polished and unpunctured; fringed on either side with long fulvescent 

 hairs,— which become gradually longer, and more and more inwardly convergent, from about the 

 second segment ; and with its edges raised into a keel on either side of the hinder portion of the 

 fifth segment, and abruptly terminated posteriorly in the form of two prominent teeth) ; with 

 the fifth segment obliquely scooped out between the lateral keels, and also emarginated ; and 

 with the sixth segment deeply notched (subtriangularly) in its centre. With the four hinder 

 femora slightly incrassated,— the joos/en'or/jafr having their under edge clothed with denser and 

 longer pubescence. 



Female, with the breast beneath much less deeply impressed, and without any additional pile. With 

 the abdomen beneath unimpressed; the fifth segment being simple, and the siith rounded and 

 produced, — though with its extreme apex minutely notched. And with the four hinder femora 

 not at all more incrassated, nor iha posterior jiair more densely pubescent, than the rest. 



Apart from the male distinctions, which will be gathered from the above dia- 

 gnosis, the present Stenus may be immediately recognised from its few Madeiran 

 allies by its large and robust form, and by its deeply and rugosely punctured (and 

 comparatively unpubescent) surface. It is tolerably common throughout the 

 intermediate altitudes of the island, occurring in much the same localities as the 

 S. guttnla, — though more frequently perhaps on the damp and muddy ledges of 

 the rocks (in the vicinity of the small streams and waterfalls) than by the margins 

 of the larger rivers. I have taken it both at Santa Anna and in the Eibeiro de 

 Santa Luzia in sufficient abundance, during the spring and summer months. It 

 is found in most parts of central Europe (England, France, Germany, Switzerland, 

 Austria, &c.), — often in company with the 8. speculator* of Erichson, to which it 

 is very closely allied. 



469. Stenus undulatus, WoU. 



S. niger nitidus, parce et leviter punctatus, dense subfulvescenti-pubescens, capite magno, prothorace 

 obovato valde insequali et leviter canalieulato, elytris valde undulato-inaequalibus, palpis, antennis 

 pedibusque testaceis, femoribus ad apicem late obscurioribus. 

 Mas, abdominis segmentis quinto et sexto subtus obsolete sinuatis, illo in medio late sed leviter 



* The S. providm may however be recognised from the S. speculator, not only by the abdomen of its 

 males (which has the sixth segment more deeply and acutely notched, and the longitudinal impression, 

 instead of being confined to the fifth, traceable throughout the h&s&Xfive), and by the tipo hinder femora 

 only, instead of four (of that sex), being densely pubescent ; but likewise by its forehead being a 

 little more excavated, its prothorax more evidently channeled on the disk, and by its antenuffi being more 

 decidedly black and its legs of an altogether obscurer hue. In the northern type moreover the palpi 

 of the .S". providus are almost invariably iufuscated at their extremity (whilst those of the 8. speculator 

 are immaculate) : but this distinction does not appear to hold good in the Madeiran specimens, which 

 have then- palpi generally entirely pale. 



