Vol. XVII. No. 421. 



THE AGRICULTDJIAL NEWS. 



187 



adults which fly up at it.s approach and are trapped by the 

 sticky material. The rough, unevea nature of many of the 

 Cuban pastures, large areas of which have been in timber, 

 makes the use of a machine of this type somewhat difficult. 

 The employment of the green niuscardine fungus, which is 

 present in Cuba, is also sugge.sted as a further remedy against 

 the froghopper. 



THE SUGAR-CASE MEALY-BUG (PiClldoCOuUS SaCchaii). 



This insect causes serious injury to sugar-cane in some 

 parts of Cuba by attacking both the roots and the stalk. In 

 mild infestations it produces a stunted appearance in the 

 canes, but in certain areas the mealy bugs occur in such 

 numbers as to kill the canes outright. It is stated that in 

 some places the poor cane is burnt over, the fields ploughed. 

 and new cane is planted, but usually replanted cane fail.'- to 

 grow siocu the young shoots are killed oflF by the swarm.-- of 

 mealy-bugs. It was at first thought probable that other 

 factors might have contributed to the Heath of the cane.s, and 

 a thorough examination was niatle 



Termites were abundant; in many places among the 

 roots and stubble of the cane, but only in dead parts. A few 

 white giubs were found, but there was no evidence of injury 

 to the roots of the cane by these insects. Fungi were not 

 present in quantity to cause them to be suspected of injuring 

 healthy plants. The soil conditions were found to be as good 

 in the infested areas as in the non-infested. There only 

 remained the mealy-bug to be held responsible for the trouble. 



This pest is considered to be tbe most serious insect 

 problem in relation to sugar-cane in Cuba, and further study 

 is urged in order to determine the exact distribution of this 

 insect, and to discover methods for its control. 



J.C.H. 



THE ENZYMES OF SOME TROPICAL 

 PLANTS. 



A paper on the above subject by Harvey C. Brill, Chief 

 of the Division of Organic Chemistry, Bureau of Science, 

 Manila, appears in Tropical Life, April 1918, from which 

 the following is mainly taken. 



An interesting part of biological chemistry is the study 

 of enxymes and their properties. Much is known regarding 

 enzymes, but much is still to be discovered with regard to 

 their functions in the growth of the plant, and their effect 

 on digestive processes when taken into the human body along 

 with food. 



Some of the foods we are accustomed to eat uncooked 

 contain enzymes of various kinds, and in different quantities. 

 For example, Chittenden has investigated the pineapple, and 

 studied the proteolytic enzyme present in it. He calls this 

 enzyme bromelin, from the botanic name of the family of 

 plants to which the pine-apple belongs. Bromelin disjests egg 

 albumen and blood fibrin. A rennet like ferment is associated 

 with bromelin. Instead of purchasing pepsin at druggists' 

 shops, which in many cases is worthless, because of faulty 

 preparation, Mr. Brill suggests that it would be more prohi- 

 able and agreeable to dyspeptics to purchase and consume 

 pine-apples. 



Another proteolytic enzyme is papain, which is obtained 

 from the fruit of the papaw. Mr. Brill .says that the ripe 

 papaw fruit has all the virtut s of the drug sold as papain, 

 and besides is a delicious fruit. It is certain that this 

 opinion is widely held in the West Indies, and it is claimed 

 in these islands that many dyspeptics have been cured, or at 

 any rate very much benefited, by regularly partaking of ripe 

 papaws along with their meal>. Papain is considered to be 

 indentical with, or »t least to reM-mble, bromelin very closely. 



The banana has rf cently been tliorouulily investigated 

 for enzymes. This fruit is rich in ferments, giving evidence 

 of the presence of enzymes which influence u, ; digestion of 

 starch, sugar, proteins, and fats. Thus banan.is eaten along 

 with breakfast aids the digestion of all the materials which 

 generally compose that meal. 



The mango also contains a proteolytic enzyme which 

 has properties similar to those of bromelin. 



It would thus appear that these four prominent fruits 

 of the tropics, the pine-apple, papaw, banana, and mango 

 have a positive food value other than that of nutrition, in 

 that they aid in the digestion of other f(jods. 



The simple synthetic food tablet which was to carry the 

 necessary food elements -protein, fat, and carbohydrates — ■ 

 in the relative proportions demanded by the human body for 

 its growth, development, and performance of its daily duty, 

 must now be relegated to the dreams of pseudo-science. 

 The process of assimilating food is a much more comple.x 

 one than was once believed, and the perfect food of the 

 future will hardly be prepared in tablet form. 



A BERRY POISONOUS TO FOWLS. 



The order of plants, Solanacou-, to which the potato 

 belongs, contains species possessing very different qualities. 

 Some are extremely poisonous, and others, as are well known, 

 are among the most nutritious of vegetables. These differing 

 properties occur in different species even of the same genus, 

 as is the case in the genus Solanum. The berries for instance 

 of Solanian inf/ongeim, known as the egg plant or Melongene, 

 are a wholesome article of food. The berries of other well- 

 known West Indian species, such as tho.se of the bitter berry 

 or canker berry (Soiaiium igneum), although distinctly bitter 

 in flavour, are, as far as the writer of this note knows, per- 

 fectly innocuous, and are quite freely eaten by children in 

 the West Indies without any deleterious effects. There are, 

 however, some species of this genus the berries of which are 

 very poisonous. Among these is So.anum staforfhianuin. 

 This is a South American species, cultivated as a climber in 

 West Indian gardens, and is one of the lighter varieties of 

 climbing plants, with deeply lobed leaves as much as 6 inches 

 in length, and produces graceful racemes of light blue flowers, 

 the expanded petals of which measure about J-inch across, 

 with a centre of bright yellow coherent anthers, making a 

 very pretty contrast These flowers are succeeded by bunches 

 of berries which turn a brilliant red when ripe, each about 

 i-inch in diameter, and containing many seeds, which are 

 covered with a dense mass of hairs. 



In the West Indies these berries have always been 

 considered poisonous, and children are warned against them. 

 It appears however that these berries have proved to be very 

 poisonous to fowls in (Queensland, where also the plant has 

 been introduced for ornamental purposes. In the AustrixHan 

 Sugar Journal, March 7, 19 IS, it is stated that Mr. Henry 

 Tryon, Government Entomologist and Vegetable Pathloogist, 

 has been investigating cases of poisoning amongst fowls which 

 he attributes to the berries of this [plant. These are consumed, 

 it is stated, with avidity by fowls. Under these circumstances, 

 it will be well for poultry keepers to be aware of growing 

 this plant in situations where their fowls can obtain access to 

 the berries. It is not stated whether the berries, which fall 

 only after they are almost quite dry, -till retain in their dry 

 condition this poisonous property. Caution, however should 

 be used in allowing poultry to eat the berries even when drT 

 on the ground. 



