Miscellaneous. 1 59 



a gemiQal receptacle, which is always empty. The ovaries are com- 

 posed of a few tubes, always destitute of ova. lu those herma- 

 phrodites of which the abdomen presents exactly the form peculiar 

 to the drones, the copulatory apparatus exists in as complicated a 

 form as usual ; the vas deferens and the testes nre also well formed, 

 and the latter are full of speruiatozoids. 



A frequent form of hermaphroditism consists in the simultaneous 

 presence on each side of a few testicular coils and ovarian tubes, 

 whilst the epididymis and male copulatory apparatus are well deve- 

 loped, and an imperfect poison-apparatus is also present. In this 

 case spermatozoids are formed, but no ova. 



It is interesting to note that these hermaphrodites are seized by the 

 workers at the moment of their issuing from the cells, and thrown 

 pitilessly out of the hive. Their integuments being still soft, they 

 cannot fly, and consequently soon perish. The queen of the hive 

 which furnished these hermaphrodites is of the pure Itahan breed, 

 and five years old ; she presents no abnormal appearance externally. 



Professor Siebold, although unable positively to explain the mode 

 of production of these hermaphrodites, does not consider that they 

 present a phenomenon incompatible with the parthenogenetic theory 

 of Dzierzon. In other animals the semen gives the impulse to the 

 development of the egg ; the result of the influence of the semen of 

 the drone is to impress the female character upon the ova, which, 

 if not fecundated, would produce male individuals. The author 

 thinks that we may assume a certain minimum quantity of semen to 

 be necessary for the fecundation of an egg. In most animals « 

 quantity of semen inferior to this minimum, of course, exerts no action, 

 and the egg is not developed ; but in bees, whose ova are capable of 

 development without fecundation, things must go on difl^erently. 

 Normally fecundation transforms the male egg of the bee into a fe- 

 male egg. Tiiis conversion probably re<juires the action of a certaia 

 number of spermatozoids; but if some accidental circumstance prevents 

 the necessary qiumtity of spermatozoids from penetrating the vitellus, 

 the egg, without being completely converted into a female one, will 

 nevertheless be disturbed in its development in such a way as to pro- 

 duce a mixture of the characters of the two sexes. — Siebold and 

 K&lliker'a ' Zeitschri/t; 1864, p. 73. 



On the Airial Root* of the Orehidea. 

 By H. Lritgeb. 



The cellular tissue forming the outer layer of the aerial roots of 

 tropical Orchidese, and described by Schleiden under the name of 

 the " root-envelope," is neither placed above the epidermis, as sup- 

 posed by Schleiden and Chatin, nor, as asserted by Schacht and 

 Oudemans, the outer part of the primary bark, and therefore covered 

 by the epidermis, but a cellular structure in the epidermis. The 

 root-envelope is not developed from a cellular tissue already deposited 

 beneath the epidermis by the primitive parenchyma of the vegeUtive 

 cone, but subsequently and directly from the epidermis by the divi- 



