ZOOLOaY A.ND BOTANY, MICROSCOPY, ETC. 



383 



Fig. 95. 



noted. The cocoons of the ChloephoridaB have a sharp ridge at the anterior 

 extremity ; this ridge is formed by two closely fitting edges, forming a 

 valve, this can be easily opened from within, to allow the imago to escape, 

 but will not yield to any ordinary pressure from without. The larva of 

 Paniscus cephalotus, parasitic on the larv^ of Dicranura vinula, is also 

 described, as well as its development. The author deals with the distribution 

 of derived plant pigments. These are found to be differently distributed in 

 various larvge. In some Noctuse green pigments are dissolved in the blood ; 

 in the green Sphingidae, the pigment passes from the blood into the cells of 

 the hypodermis. Before pupation the pigments are withdrawn and dissolved 

 in the pupal blood. Various tables are given bearing on the loss of weight 

 in the pupa immediately after throwing oif the larval skin. This loss of 

 weight is chiefly due to evaporation from the surface of the body, but also to 

 the active muscular effort of pupation, entailing 

 loss of water, and carbonic acid through the 

 tracheal system. On the other hand, there must 

 be a gain of weight due to absorption of the 

 oxygen, which is stored up as the oxidized pro- 

 ducts of nitrogenous metabolism, which fill the 

 digestive tract of the pupa and imago within it. 



Geometrical Construction of the Cell of the 

 Honey-bee.* — Prof. H. Hennessey gives a figure 

 and the method by means of which the lozenges 

 composing the cell can be obtained. 



On a straight line take a part A D, and lay 

 off D C = 2 A D. From D erect a perpendicu- 

 lar, and with a radius AC = BAD cut off DP : 

 then AC and AP are sides of the lozenge 

 A C E P. From this, the remaining two 

 lozenges, and also the six trapeziums can be 

 obtained. The triangular pyramid which termi- 

 nates the bee's cell may be inscribed in a sphere whose diameter is three 

 times the size of one of the edges of the pyramid. The diameter of this 

 sphere can be found by a mathematical formula which he gives. 



Anatomy and Histology of Culex nemorosus.j — Herr W. Easchke 

 states that in general habit the larva of Gulex nemorosus resembles the 

 aquatic larva of the Nemocera ; the cylindrical body consists of twelve 

 somites, the first three of which are fused to the thorax. The strong 

 chitinous tubes which project from the penultimate somite are very striking ; 

 a valvular apparatus not only enables the animal to remain at the surface 

 of the water, but also serves to close the tracheal endings in the siphon ; 

 these have also a peculiar constriction, the mechanism of which is con- 

 nected with the valves and serves as a second closing-organ. Eespiration 

 is also effected by anal gill-plates, and by an exchange of gases through 

 the integument ; the rectum is provided with means for containing a large 

 number of tracheal branches. In addition to the two pairs of eyes, the 

 larva has various sensory hairs, which are found not only on the antennsB 

 and epipharynx, but are also specially arranged over the whole body. 



Males of Lecanium hesperidum, and Parthenogenesis. | — M. E. Moniez 

 has found the males of L. hesperidum in a large number of females examined 

 between September and February : each male was in a separate ovarian 



* Proc. Roy. Soc, xli. (1886) pp. 442-3 (1 fig.). See this Journal. 1886, p. 234. 

 t Zool. Auzuig., X. (1887) pp. 18-9. J Coinptes Rcndus, civ. (1886) pp. 448-51. 



