'rmm mm.mmicm.m mmw jq-ukkki^. 



635 



several in which the corollas had just 

 loosened, it immediately began to sip 

 the little drops of nectar which still re- 

 mained attached to the base of the 

 corolla. It is certainly a clear case, for 

 the insect tried in every way to get nec- 

 tar, except by perforating the corolla. 



The examples of flowers perforated 

 by Banibas tenrMris show that it mainly 

 pierces those from which it cannot get 

 nectar in a normal way. Muller has 

 found this interesting difference be- 

 tween its visits to flowers on the plains 

 and valleys, and to those of alpine and 

 sub-alpine regions ; that while in the 

 lower regions it perforates many flowers 

 where the nectar is in part accessible 



to it others are visited in a normal 



way in alpine regions. 



Muller also found a constant differ- 

 ence in the length of its tongue. In 

 the Alps its tongue was usually 8 11 

 mm. long, while in the lowlands only 

 7-ii mm.long. JJonihustcrrifiti-i:^ is one 

 of the most abundant of European 

 humble-bees, and this is perhaps one 

 reason why it uses these illegal means 

 to get nectar. J3ut B. ma^tnimtio', as 

 Muller's investigation shows, is the 

 worst enemy to alpine flowers. Not- 

 withstanding that its tongue is of 

 sufllcient length to enable it to reach 

 the nectar of some flowers it per- 

 forates them, and only pollinates such 



flowers as it could not well perforate 



unless it were to go to more trou^ile 

 than getting the nectar in a normal 

 way involves. . . . 



Carpenter Bees and Flowers. 



The Carpenter bees, belonging to the 

 genus A'ly'orrfj/d, do considerable injury 

 to flowers in more southern latitudes, 

 where thev abound. 



Xylocopa Virginica, according to 

 Cresson, is found in the middle, south- 

 ern and western States, and of the 27 

 species of this genus mentioned in his 

 catalogue, this is the most northern, 

 and has the widest distribution. The 

 species no doubt causes considerable 

 annoyance, as :Mann, Ryder, and Miss 

 Murtdfeldt have shown. Mr. Maun 

 was the first to describe one method 

 which it uses to perforate flowers, in 

 which ■• the insect applies its sharp and 

 wedge-shaped maxillae to the grooved 

 surface of the tube, aad splits this open 

 3 or 4 mm. from the base." 



Dr. Schneck and Mr. Van Ingen each 

 record several cases in which the tube 

 of the corolla had longitudinal slits, 

 but as perforators they found humble- 

 bees (lli)iiibu.< .■']. As these slits corres- 

 pond so well to the slits I found on tlie 

 tube of the corolla of Phlomis, 1 bring 

 them up in this connection. I fre- 

 quently found this Xylocopa in the act 

 of making longitudinal slits in the tube 

 of the corolla of Phlomis tuberosa. The 

 insect applies its powerful mandibles 

 against ihe tube of the corolla until it 

 gains entrance, then, thrusting its 

 maxilliE in as far as it can in a longi- 

 tudinal direction, the tissue yields 

 easily, so that longitudinal slits are the 

 result. At other limes the mandibles 

 are drawn backward and forwnrd, thus 

 causing longitudinal slits. The num- 

 ber of slits varied from one to three. 

 The insect did not take much trouble 

 to And the old slits, but went directly 

 at making new ones, as it seemed to be 



easier for it to do this than to waste 

 time in looking for the old ones. 



'n'u»i>s Perloratlng Flowers. 



Wasps also perforate flowers, es- 

 pecially such as are adapted to this 

 class of insects.... Mr. Robertson has 

 reported to me several interesting cases 

 where wasps use perforations, and, at 

 least in one instance, make them. At 

 Orlando, Fla., he found Ave species of 

 wasps, which sucked the flowers 

 through perforations, which are at first 

 very small, but finally large and irreg- 

 ular. At Clinton, Mo., he observed 

 that Odynerus Foraminatus made per- 

 forations in the tube of the corolla of 

 Monarda Bradburiana, which, as he 

 thinks, were made by the wasp taking 

 the tube between her jaws and cutting 

 towards the mouth of the corolla, thus 

 loosening a triangular piece which 

 could be closed over the opening. In 

 the Botanic Garden I frequently found 

 the flowers of this species perforated, 

 but the perforations were in the form 

 of longitudinal slits. 



While wasps do not generally per- 

 forate flowers, they are not above using 

 those perforated by species of Bombus 

 and other insects; for these, in their 

 rapid visits to flowers, are certain to 

 leave some nectar. Insects much lower 

 in the scale than wasps, frequently use 

 the perforations made by species of 

 Bombus, as Muller has shown to be the 

 case in a small Ichneumon fly which 

 eagerly sought the nectar left in the 

 flowers 



Ants and Beetles GatUering Honey. 



Ants are especially fond of saccha- 

 rine matter, and are frequent visitors 

 to flowers, but only for nectar. Their 

 visits are entirely injurious to the 

 plant. They frequently gnaw parts of 

 the flowers, and make irregular holes, 

 thus gaining an entrance, or they use 

 the perforations made by other insects. 



Beetles, although not high in the 

 scale of development, and certainly 

 low as far as the adaptation of flowers 

 and their pollination is concerned, 

 show, in a few cases, some ingenuity 

 in getting at nectar, as Muller found to 

 be the case with Cetonia Aurata, which 

 feeds on delicate parts of various 

 flowers, is especially fond of nectar, 

 and was found on the flowers of Con- 

 vallaria Polygonatum eating its way 

 from the top of the perianth to where 

 the nectar is found at the base of the 

 pistil, where it began to feed on the 

 nectar-secreting gland until the wall of 

 the ovary was reached, when it left the 

 flower. 



The acute observer Sprengel found 

 that large numbers of the flowers of 

 Symphytum Oftlcinale were perforated 

 by one of the flower-beetles, and that 

 ants used these perforations. :Mr. B. 

 M. Vaughn, who found the flowers of 

 Corydalis Aurea perforated at Madison, 

 AVis.,isof the opinion that these per- 

 forations were made by one of the 

 flower- beetles. 



Birds that Pcrrorate Flowers. 



It is not strange that birds should at 

 times perforate flowers, since so many 

 flowers are well adapted to pollination 

 by them. Prof. Trelease mentions 



that, according to Prof. W. A. Henry, 

 the humming-bird probably perforated 

 the flowers of Tecome Radicans. Dr. 

 Schneck and George Sprang have found 

 these perforated, but the latter found 

 ants gnawing through the corolla In 

 the ilotanic Garden there was hardly a 

 single fully opened flower of this 

 species which did not have a few slits. 

 Prof. Beal reports that Mr. Ilollings- 

 worth found the flowers of Fuchsia 

 pierced through at the base of the 

 calyx- tube and robbed of their nectar. 

 Mr. Robertson writes me that he has 

 seen the humming-bird force its bill 

 into a flower-bud, so that the lobes of 

 the corolla had not been separated, but 

 merely cut through. Prof. Beal watched 

 carefully for two seasons the flowers of 

 the Missouri Currant, seeing large num- 

 bers of bees collecting nectar from 

 holes made in the calyx-tube; yet, after 

 careful examination, he has never seen 

 honey-bees make these holes, but sev- 

 eral times noticed the Baltimore oriole 

 passing over the bushes and giving 

 each of the fresh flowers a prick with 

 the tip of its beak. No other bird hav- 

 ing been seen doing this, he concluded 

 that it is the work of the Baltimore 

 oriole, while the honey-bee takes the 

 gleanings after the oriole. 



How Floivers are Perforated. 



I have alluded to the manner in which 

 Xylocopa makes perforations ; I must 

 also describe how this is done by Bom- 

 bus and Apis : 



The mouth-parts are somewhat com- 

 plex : the mandibles or upper jaws are 

 developed for the purpose of biting; 

 the maxillie and labium are brought 

 into use when the bee takes a liquid 

 into its pharynx. The maxillte are 

 situated on each side of the labium, 

 and consist of a flattened stipe at the 

 base, then the rudimentary maxillary 

 palpi, and from the stipe projects the 

 triangular and deeply grooved lacinia. 

 When the maxillEe are brought close 

 together, a tube is formed which opens 

 into the pharynx. The labium or lower 

 lip consists of a central portion and 

 two pairs of appendages, the para- 

 glossic and labial palpi. The central 

 portion of the labium is divided into a 

 basal portion, the mentum and a termi- 

 nal portion, the ligula. " The mentum 

 is hinged to the submentum, which in 

 turn is hinged to the maxillie by two 

 chitinous rods." The labial palpi are 

 deeply grooved, and when brought to- 

 gether form a tube. 



In flying from flower to flower the 

 insect carries its sucking apparatus 

 stretched forward so that it is enabled 

 to put it directly into the flower. The 

 mouth-parts of the bee are held in a 

 similar way when the tender cellular 

 tissue is pierced with the tips of its 

 maxillffi. While many humble-bees are 

 addicted to boring the tubes of corollas, 

 they also resort to bitting the tissues 

 of the flowers by the aid of their 

 mandibles. 



Fertility of Perforated Flowers. 



Tlie opinion is current that perforated 

 flowers are not as productive as un- 

 perfoiated ones. Delpino has shown 

 that some perforated flowers are ab- 

 solutely sterile. Ogle states that many 



