TRANSACTIONS OF SECTION D, 



689 



spondence in tlie figiii'es is due to extreme cases. The following are the statistics 

 relating to the points b, c, din n for ten pair of Paramecium : — 



The following statistics, also in /x, relate to the points b, c, d for five pair of 

 Stylonichia pustulata : — 



The measurements are for full-grown forms, but the microphotograplis of Para- 

 mecium show variation at dift'ereut stages of development. The variation was 

 traced into the succeeding generation. 



From the fact that there is variation in binary fission we get additional reasor. 

 for holding witli Engelmann, Maupas, and Biitschli, as against Gruber, that the 

 vegetative phase of the life of the clliata is primary, and we are enaljled to see 

 in conjugation simply a device whereby the waste involved in that process can 

 "be refunded. 



3. On a neio Form of Luminous Organ. By W. E. Hoyle, M.A. 



4. Notes on Some Bornean Insects. By R. Shelford, M.A. 



Orthoptera. — Two species of aquatic coclivo&chQS—Ejjilampra sp. and a 

 Pamesthiid — were found at the base of a waterfall on Mount Matang, Sarawak. 

 All the specimens were immature, but adult forms have been discovered by Mr. 

 Anuandale in the Malay Peninsula ; the females are apterous. These cockroaches 

 swim and dive well, h\x% are soon drowned if prevented from rising to the surface 

 to breathe, agreeing in this characteristic with most adult aquatic insects. When 

 at rest the body of the cockroach is almost entirely submerged, the tip of the 

 abdomen alone projecting above the surface of the water ; the abdomen moves 

 gently up and down, and every 30-40 seconds a bubble of air issues from the 

 prothoracic spiracle on each side. Appai'ently the terminal spiracles are purely 

 inspiratory in function and the prothoracic expiratory. 



The eggs of the stick-insects of the genera Necrosia, Marmessoidea , and Agon- 

 dasoidea are not seed-like as are the eggs of other genera ; twenty or thirtv only 

 are laid, and these are stuck in close-set rows on the leaves of the food-plant, 

 not dropped promiscuously on the ground. The eggs are long and somewhat 

 tiattened cvals, white or cream-coloured, with a delicate network of black pigment 

 over the upper surface; there is no capitulum. The young hatch out in 10-14 



