358 Miscellaneous. 



A new species of Apus, A. longicaudatus. By John LeConte, F.L.S. 



Pale brown : buckler large, thin, gibbous, nearly round, carinate 

 on the middle of the back, deeply emarginate behind, the edges of 

 the emargination fringed with short spines : eyes three, simple, the two 

 anterior larger, approximate, somewhat lunate, the third one round, 

 placed in the middle behind the two others : antennee very short, in- 

 serted near the mandibles, two-jointed, joints cylindrical, subequal, 

 the second joint somewhat acuminate and naked at the tip : first 

 pair of feet, or as they have been called, exterior antenna?, furnished 

 with four articulated filaments ; of these filaments, the outer one is 

 longer than the body, the next half the length of the first, the third 

 about one- third the length of the second, and the fourth very short : 

 the other feet, amounting to ten pair, are flattened, trifid at the tip, 

 the intermediate division being the longest, furnished on the inner 

 side with a short branch, and externally with a broad lamina ; below 

 these feet are twelve pair of laminae, the five anterior pair larger, the 

 seven smaller pair reaching to the vent, which is covered by the last 

 pair; these lamina? are complicated in their structure, and ciliate 

 with short hairs : tail long, consisting of sixteen joints counting 

 downwards from the vent, the last one the longest, somewhat cori- 

 aceous, emarginate, and ending in two long articulated naked fila- 

 ments ; the joints of the tail and of the filaments are furnished each 

 with a row of small spines, which run entirely round. 



Length to the end of the tail, 1*5 of an inch ; of the buckler, '65 ; 

 breadth of the same, 7. 



Of the habits of this animal we know but little ; it was found in 

 immense numbers in a small shallow lake on the high plateau be- 

 tween Lodge-pole Creek and Crow Creek, north-east of Long's Peak, 

 in the Rocky Mountains : they were swimming about with great ac- 

 tivity, plunging to the bottom and rising to the surface. All of them 

 that were caught appear to be males, at least none of them have any 

 ova attached : the common species in Europe, A. cancriformis, on 

 the contrary, has never been found but of the opposite sex. — Silli- 

 man's American Journal, Sept. 1846. 



Structure of the Trunk q/" Cycas circinalis. 



From the examination of some old trunks of Cycas received from 

 Java, Prof. Miquel draws the following conclusions : — 1. The stem 

 of Cycas is composed of two sorts of elementary organs, viz. paren- 

 chymatous cells and dotted vessels, agreeing in this respect with the 

 structure of Coniferce. 2. In the distribution of these elementary 

 organs, it differs greatly from that of Coniferce : the wood is disposed 

 in irregular concentric layers, confluent at certain points, unequal, 

 having no relation with the buds, separated by broad layers of cel- 

 lular parenchyma. 3. In the development of the tissues there are 

 several peculiarities which are not found in Coniferce ; for instance, 

 in the increase of the trunk in length from the summit only, in the 

 preponderance of parenchymatous cells, in the ligneous parts being 

 traversed by cortical parenchyma, &c. 4, In this acrogenous growth 



