Vol. XVII. No. 416. 



THE AGRICULTURAL NEWS. 



107 



entirely confined to the earlier stages. The earliest hatched 

 and stronger members of an egg cluster often feed on the 

 weaker ones, or on some of the eggs, while the adults, both 

 males and females, devour the eggs wtjenever chance offers. 



This species of mole cricket usually moults eight times 

 after the egg stage, although occasionally males are recorded 

 as moulting only seven times before reaching the adult con- 

 dition. The younger stages are somewhat similar to the 

 adult in general appearance. The for«-legs are slender at 

 first and the wings are undeveloped, but iwith each succeeding 

 stage the nymph becomes more like the adult, the fore-legs 

 gradually developing and growing specialized for digging, 

 while the wings increase in size with each moult. Moulting 

 as a rule is carried out in a specially constructed underground 

 cell similar in shape to the egg-chamber, but it sometimes 

 takes place above ground. 



It was found that the entire period from the egg stage 

 to the adult averaged 295 days for nineteen individuals. 

 It is estimated that about a year is required for the full 

 development of a generation. : 



ENEMIE.S. 



No true parasites have been found to attack the changa 

 in Porto Rico, but this insect has a number of predaceous 

 enemies, the combined cttbrts of which, however, are unable 

 to keep it under control- 



The writer states that the most efficient enemies of the 

 changa are to be found among the native birds. The two 

 most important birds in this connexion are the Cuban green 

 heron {Butoriiks viresccns ciil'aniis), amd the Porto Hican 

 sparrow hawk (Falco sparreriiis loiiiiaeuhi). Among other 

 birds mentioned as feeding on the mole^iricket in Porto Rico 

 are the little blue heron or gaulding {Florida coenika 

 coenilcsceiis), the tick bird or ani {Cn>fo/>/iai;a ani), and the 

 rain bird or ^ilui^ {Tvi annus (.hiiniiu'ceitsis ifi>mi?iiir/isi's). 



It may be mentioned here that in St. Lucia the West 

 Indian mole cricket is attacked andeated by the above species 

 of birds or by varieties of the same species. In St. Vincent 

 the gree-gree or chicken hawk {Biiftu nntillanini) was found 

 by Clark to feed largely on mole crickets. This bird formerly 

 fed mainly on lizards, but owing to the fact that the lizards 

 have been greatly reduced in numbers by the mcngodse, it 

 seems that mole crickets have become the prey of the 

 gree-gree. 



Fowls are very useful in feeding on mole crickets 

 where land is being cultivated, and hogs, in addition to 

 devouring white grubs, also eat the changa. 



Among other probable enemies of this mole cricket 

 mentioned by the writer are the large burrowing lizard or 

 'siguana' {Ameiva txit/), the common centipede {Sco/o/endra 

 alUrnans), a predaceous carabid beetle {Ca/vsoma a/kriiai:s), 

 and the larvae of the luminous elaterid beetle {Pyrophoms 

 lumlnosus). 



J.C.H. 

 ( To be iO>i/iinicd.) 



STORING OF SWEET POTATOES AND 



OTHER VEGETABLES. 



It is well known that a great difficulty in connexion 

 with sweet potatoes as a food supply is that of stor- 

 ing them for any length of time. At a meeting of the 

 Tacarigua District Agricultural Society in Trinidad on 

 February 23, reported in the Purl-oJ- Spain Gazette, February 

 26, Mr. A. F. Miller read a paper on the preservation of fruit 

 and vegetables, in which he made some useful suggestions on 

 this subject. 



He said that the best way to deal with large quantities 

 was by hilling and banking. This might be carried out 

 under a shed, or other me^ns could be used to prevent 

 exposure to weather. Lay dut the ground (which must be 

 dry) with a ditch round the space required; put a good layer 

 of straw or trash; then put the potatoes (or other roots or fruit 

 to be preserved) in the form of a mound of triangular section; 

 cover the whole heap with a, liberal layer of straw or trash, 

 and then cover with- damp earth, picking firm with a spade. 

 ^Vhere large quantities were . stacked, a zinc pipe perforated 

 with I -inch holes should \s& placeil upright through the 

 centre of the heap thus .allowing surplus moisture to 

 escape while the potatoes were going through their sweating 

 process. On a small scalq the best way was to obtain 

 a number of empty cement barrels, and place at the bottom 

 of each a 3-inch layer of dry sand, then a layer of potatoes, 

 then another layer of sand, and so on, until full, putting 

 a layer of about 4 inche.s of sand on top; this would keep 

 the tubers quite sound for six months: and only one 

 barrel need be opened at a time. These methods were appli- 

 cable to potatoes, yams, tannias and all other root crops 

 (except cassava). 



The same method might be employed in the storage of 

 many fruits, such as mangoes and citrus fruits, as well as 

 many kinds of other vegetables, such as cucumbers and 

 melongenes. Such fruit for storage should be picked in 

 a green-ripe or 'full' condition. 



With regard to breadfruit and cassava, the following 

 hints seem useful. As to breadfruit, in the Marianne 

 Islands, the simple and effective method was ustd of peeling, 

 coring, slicing, and baking the green-ripe fruit in dry 

 ovens. These dried slices ate like biscuits and kept well. 

 With regard to cassava, without discussing the well-known 

 methods of starch, farine and tapioca preparation, the writer 

 described some of the less-known ways, such as preservation 

 for table use by slicing and sun drying, and finally baking in 

 ovens like breadfruit slices. 



AMERICAN POTASH. 



The Journal of the Rm/al Societi/ of Arts publishes the 

 following particulars in connexion with the potash supply in 

 the United States of America: — 



The production of potash in the United States was 

 greatly increased in 1916, according to a report of the United 

 States Geological Survey. The total production of potash 

 salts and potash products in the United States in 1916 repre- 

 sented about 10,000 short tons of pure potash, with a net 

 value at point of shipment of at least $3,500,000. This is 

 ten times the value of the production reported for 1915, but 

 the figures submitted by many of the producers represent 

 only a start made towards the end of 1916. 



The potash produced in 1916 was derived from the 

 following sources: — 



Mineral sources. — Natural salts or brines, 3,850 short 

 tons; alunite and silicate rocks (including furnace dust 

 recoveries), 1,900 short tons. 



Qrijanic .sowrcts. — Kelp, 1,100 short tons; pearlash 

 (mostly from hardwood ash), 220 short tons; miscellaneous 

 industrial waste, 1,750 short tons. 



The largest output comes from the Nebraska alkali lakes, 

 but the natural saline deposits elsewhere are beginning to 

 make important contributions. The production of potash 

 from organic sources is about half that from mincTal sources. 

 The recovery of potash from pearlash is an old-established 

 industry. 



