50 SUMMARY OF CURRENT RESEARCHES RELATING TO 



groups of syncytia, each syncytium behaving like a unit of cellulai 

 activity. The early oogonia have very definite cell walls. The 

 spermatogonial number of chromosomes for five species of Cicinchla is 

 twenty-two. The oogonial and female somatic number is twenty-four. 

 Definite pairs of chromosomes are readily recognized in .every clear 

 spermatogonial, oogonial, and somatic metaphase plate. The eleven 

 chromosomes of the first spermatocyte are very irregular in shape and 

 especially difficult to figure. Autosomes in the form of complete and 

 incomplete V's of various sizes, rings, hooks, and rods were figured 

 from side views of the spindles. The secondary spermatocyte numbers 

 of chromosomes are ten and twelve, much more uniform than those of 

 the first spermatocyte. The "sex- chromosome" appears on the first 

 spermatocyte spindle as a double body, the two elements (X, x) of which 

 are very unequal in size and loosely united. These elements neither 

 divide nor separate in the first division, but pass to one pole in advance 

 of the autosomes, giving secondary spermatocytes with ten and with 

 twelve (10 + X + x) chromosomes respectively. In the second division 

 the components of the bipartite body separate. The germ cells of the 

 female seem to contain approximately twice as nuich X chromatin as is 

 found in those of the male. J. A. T. 



Intestinal Glands in Larval Insects. — ^J. Pantel {La Cellule, 

 1914, 29, 393-429, 1 pi., 2 figs.). In larvae of PtychopteridEe there are 

 five Malpighian tubes, two directed forwards and partially transformed 

 into large sacs distended with granular calcareous concretions, the others 

 directed backwards. The minute structure of the tubes is described. 

 The tubes are bound to other structures by muscular fibres. During 

 the pupation the posterior tubes pass without disintegration into the 

 imaginal structure ; the sacciform tubes expel their contents into the 

 intestine, whence it is got rid of, and pass into the imaginal structure ; 

 the muscular fibres degenerate. The calcareous granules are to be 

 regarded simply as products of renal excretion. J. A. T. 



Dipterous Parasite of Peaches. — J. Legendre (C. R. Soc. Biol. 

 1920, 83, 8-9). Madagascar peaches are much spoiled by amber- 

 coloured maggots of Ceratitis capitata, often called the " orange fly," 

 which is well known in the Mediterranean region, in Africa, Mauritius 

 and Reunion. ' J. A. T. 



Dorsal Blood-vessel in Larval Muscids. — J. Pantel {La Cellule, 

 1914, 29, 318, 3 figs.). Description of the minute structure of the 

 posterior region of the dorsal blood-vessel in larva3 of Thrixion, 

 Comimlura and Ceromasia, showing differences in detail in these types. 



J. A. T. 



Cyrtopogon platycerus Villeneuve. — J. Escher-Kundiq {MT. 

 Schweiz. Entomol. Ge.^.^ 1919, 13, 54-9, 3 pis.). A description of the 

 hitherto unknown male of this rare predatory fly, which the author found 

 at Novaggio, in the Malcantone Valley. Its sex dimorphism is compared 

 with that of C. longiharhus Low., and a careful description is given of 

 both sexes. J. A. T. 



