Miscellaneous. 327 



in growth, in order that its internal development may be accom- 

 plished. When this is the case, it becomes manifest that the body, 

 sarcode is, so to speak, a vital product of the nucleus. Moreover, 

 it is from it that the flagella originally arise. In the same way, 

 it is only by a complicated and beautiful series ef delicate activi- 

 ties in the nucleus that the wonderful act of fission is initiated, and 

 in all probability carried to the end. So, too, all the changes that 

 go with fertilization and the production of germs are a series of 

 correlated activities, due, at the beginning at least, wholly to the 

 nucleus." All the stages are figured, from the bare nucleus (origi- 

 nal germ) down to the amoeboid form prior to conjugation with 

 another individual, and the conjoint formation of a quiescent mass 

 of protoplasm, which finally gives rise to a cloud of protoplasmic 

 dust, as it were, which represents the germs or nuclei of yet un- 

 developed individuals, thus completing the entire cycle. — Jour, of 

 Boy. Mic. Soc. 



The Digestive Process m some Khizopods. — Physiology, as a 

 field for original investigation, has been recently entered by ladies. 

 Miss Greenwood, Demonstrator of Physiology, Newnham College, 

 Cambridge, has published a paper on the above subject. Her in- 

 vestigations were confined chiefly to the two interesting forms 

 Amoeba and Actinosphserium. The latter, as is well known, has a 

 spherical protoplasmic body, honeycombed with numerous vacuoles, 

 and with filiform pseudopodia protruded from its surface. Her 

 method of work may be described as chemico-microscopical. The 

 digestive process is considered under the heads : (a) Ingestion, (6) 

 Digestion, (c) Egestion. In these two forms, no digestive ferment has 

 as yet been found. Many accounts of intra-ceilular digestion in 

 invertebrates have been published, but not a few of them are mere 

 fragments. Miss Greenwood draws the following conclusions in 

 regard to the above-mentioned two forms : — 1. They show constant 

 and promiscuous enclosure of solid matter, which is received in 

 the vacuole of ingestion. The nature of the latter is doubtful. The 

 formation from the surrounding medium points to its aqueous cha- 

 racter ; but the rapid death of the enclosed prey, in Amoeba at least, 

 argues some influence or secretion from the enclosing animal. 2. 

 Starch grains are not digested by Rhizopods. 3. Fat globules are 

 not digested by Amoeba ; a slow digestion of them probably takes 

 place in Actinosphserium. 4. The fate of digested matter depends 

 on its character. If it is innutritious, the vacuole of ingestion dis- 

 appears ; if nutritious, it undergoes change not effected by direct 

 contact with the acting protoplasm, but by something passed out of 

 the protoplasm into what has become the vacuole of digestion, in 

 fact, a secretion. This case resembles that of the higher animals, 

 in so far that the secretion is passed into a cavity — the cavity in 



